JP2010042395A - Anion exchange resin, method for manufacturing macroporous type anion exchange resin, demineralization device, condensate demineralizer for power plants, and method for removing suspension metal corrosive product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ion exchange resin having excellent removal performance of suspended metal corrosion products including clad and colloidal fine particles, little elution, and high mechanical strength.
[MEANS FOR SOLVING PROBLEMS] A macroporous ion exchange resin having a pore volume as measured by a mercury intrusion method of 0.5 mL / g or more per 1 g of dry weight of the ion exchange resin. An ion exchange resin, characterized in that the pore radius when measured is 0.1 μm or more, and the turbidity component eluted in the shaking turbidity test of the ion exchange resin is 45 ppm or less. The pore volume as measured by the mercury intrusion method is preferably 0.20 mL / mL or more per volume in a water-wet state.
[Selection figure] None

Description

  The present invention relates to an anion exchange resin, a method for producing a macroporous anion exchange resin, a desalination apparatus, a condensate desalination apparatus for power plants, and a method for removing suspended metal corrosion products. Specifically, an anion exchange resin suitable for removing suspended metal corrosion products produced in power plant, etc., a method for producing a macroporous type anion exchange resin, a desalinator, a condensate demineralizer for a power plant, And a method for removing suspended metal corrosion products.

  In boilers and power generation facilities, various types of hot water and room temperature water are required to be desalted and purified. For example, nuclear reactors used for nuclear power generation include a boiling water type (BWR) and a pressurized water type (PWR). The former is a type in which cooling water is heated in a nuclear reactor, converted into steam and directly supplied to the turbine, and the latter is heated in the nuclear reactor and supplied to a steam generator to generate steam. The secondary cooling water is heated by a vessel, converted into steam, and supplied to the turbine. In any of the above reactors, a reactor water condensate demineralizer filled with an ion exchange resin is installed in the cooling water circulation system. As a result, suspended metal corrosion products eluted from metal materials such as pipes and salts mixed in due to leakage of seawater used as cooling water for condensers are removed, improving water quality. ing.

In recent years, removal of suspended metal corrosion products among radioactive substances from primary system water when a power plant is stopped has been a problem from the viewpoint of reducing exposure of workers.
The trace amount of metal impurities present in the water undergoes a nuclear reaction upon irradiation with neutrons emitted from the fuel, and forms radionuclides such as cobalt 60, cobalt 58, chromium 51, and manganese 54. These radionuclides are mainly present in the form of oxides attached to the components, but depending on the solubility of the oxides, they are either redissolved in water or released into water as insoluble suspended metal corrosion products. The

  Among the suspension metal corrosion products, a relatively large one is called a clad and is usually filtered and removed by a filter having a diameter of about 0.1 μm to 1 μm installed in a nuclear reactor. . In order to reduce the exposure amount of workers, further improvement of the cladding removal capability is required, and it is preferable that the removal is performed not only by the filter but also by a desalting apparatus using an ion exchange resin.

Here, in general, an ion exchange resin is a copolymer obtained by introducing an ion exchange group into a copolymer obtained from styrene and divinylbenzene, but in terms of desalting performance, the performance can be evaluated, but the cladding It was not necessarily sufficient for the filtration and adsorption of the above (refer to the prior art in Patent Documents 1 and 2).
In view of such a problem, for example, in Patent Document 1, the matrix structure of an ion exchange resin is reviewed, and a positive copolymer matrix obtained by polymerizing an aromatic monovinyl compound and an aromatic polyvinyl compound and an ester-based polyvinyl compound as a crosslinking agent is used. Ion exchange resins have been proposed.

Patent Document 2 proposes an ion exchange resin that uses a cross-linking agent that is longer than divinylbenzene as a cross-linking agent.
In Patent Document 3, condensate has excellent cladding removal performance and a small amount of organic matter eluted from the mixed bed by a special combination of a mixed bed of gel cation exchange resin and macroporous anion exchange resin. Desalination equipment has been proposed.

  On the other hand, among the suspended metal corrosion products, those having a size of 0.1 μm or less (hereinafter referred to as “colloidal fine particles”) pass through the filter for trapping the clad, so And is accumulated on the surface of the wetted part of the component. As a result, radiation was radiated from the surface of the component members, causing radiation exposure of workers during periodic inspection work, and it was necessary to make the exposure dose as low as possible economically.

As an ion exchange resin effective for removing the colloidal fine particles, conventionally, a macroporous having a large pore that allows easy entry of the colloidal fine particles in consideration of the size (˜0.5 μm or less) of the colloidal fine particles to be removed. Type anion exchange resins have been considered effective.
For example, as described in Non-Patent Documents 1 and 2, it has been considered that a large pore resin having a pore radius on the order of μm is suitable for removing colloid. As an example, an anion exchange resin having 0.5 meq / mL, a specific surface area of 7 m ² / g, a pore radius of 3.5 μm, and a pore volume of 1 mL / g has been recommended.

In addition, as a technique for improving the strength of a conventional ion exchange resin having giant pores having a pore radius of 1 μm or more, Patent Document 4 describes that a polymer obtained by performing a polymerization process is newly added and impregnated with a monomer. A method for improving the strength by polymerizing again is described.
Furthermore, as an ion exchange resin having pores and a small ion exchange capacity, Patent Document 5 and Patent Document 6 describe an ion exchange resin having an ion exchange capacity of 0.05 meq / mL or more.

Japanese Patent Laid-Open No. 5-15876 Japanese Patent Laid-Open No. 7-323235 JP-A-8-224579 US Patent Publication No. 2008 / 0237133A1 US Pat. No. 5,244,929 U.S. Pat. No. 4,871,779

Amber-hi-lites, no. 161, Spring, 1979, Rohm and Haas Company. Amber-hi-lites, No. 148, September 1975, Rohm and Haas Company.

Patent Documents 1 to 3 are techniques related to removing the cladding.
However, since the cation exchange resin described in Patent Document 1 contains a polymer of an ester-based polyvinyl compound, the cation exchange resin is easily subjected to hydrolysis during the production process and use, and the resin decreases with the strength reduction of the ion exchange resin matrix or hydrolysis. There is a problem that the amount of effluent from
In the ion exchange resin described in Patent Document 2, a linear long cross-linking agent is used in place of divinylbenzene, but this linear long cross-linking agent is very expensive compared to divinylbenzene, and is practical. is not. Moreover, since the linear long crosslinking agent of patent document 2 has low radical copolymerizability with styrene, it is difficult to manufacture efficiently.

In Patent Document 3, the macroporous anion exchange resin has a larger amount of elution than the ordinary mixed bed resin (combination of the gel type cation exchange resin and the gel type anion exchange resin), and the effluent from the resin has a large amount of elution. There is a problem that the gel-type cation exchange resin is contaminated and the quality of the demineralized water is lowered.
On the other hand, Non-Patent Documents 1 and 2 are techniques related to removing colloidal fine particles.

  In the macroporous type anion exchange resin described in Non-Patent Documents 1 and 2, colloidal fine particles are leaked and the strength of the resin is weak, so that crushing at the time of handling the resin and crushing at the time of pumping the resin slurry. There is a problem that is likely to occur. As a result, fine particles, turbidity and eluate are generated due to the crushed pieces of the resin, contaminating the mixed bed resin layer of the desalting tower, and there is a problem that the water quality is lowered.

  Moreover, in the manufacturing method of patent document 4, since it becomes a several superposition | polymerization process, it is thought that process time becomes long or a process becomes complicated. In addition, since the polymer obtained by once performing the polymerization step is impregnated with a new monomer added and polymerized again, there is a problem that the pores are blocked and the pore volume is reduced. As a result, there is a concern that the diffusibility of the colloidal fine particles adsorbed in the ion exchange resin particles is lowered and the amount of colloidal fine particles adsorbed becomes insufficient.

In addition, the ion exchange resins described in Patent Documents 5 and 6 have a very small pore radius and a very small pore volume, and are not supposed to be applied to colloidal particulate removal applications. Seem.
That is, the present invention was devised in view of the above problems, and its purpose is excellent in removal performance of suspended metal corrosion products including clad and colloidal fine particles, less elution, and mechanical strength. The object is to provide a large ion exchange resin.

Conventionally, ion exchange resins having large pores were thought to be effective in removing colloidal fine particles. However, as a result of intensive studies by the present inventors in view of the above problems, ion exchange resins having relatively small pores The present invention was completed by finding that the resin is effective for removing colloidal fine particles and clad.
In addition, the present inventor has determined that such an ion exchange resin is obtained by polymerizing a monovinyl aromatic monomer and a crosslinkable aromatic monomer using a porous agent of a predetermined amount or more, and increasing the introduction rate of ion exchange groups. It has been found that it can be obtained by making the amount below a predetermined amount.

Furthermore, it has been found that such an ion exchange resin is suitable for desalting treatment and can be suitably used for a desalting apparatus.
That is, the gist of the present invention resides in the following [1] to [15].
[1] Macroporous ion exchange resin having a pore volume of 0.5 mL / g or more per 1 g of dry weight of the ion exchange resin when measured by a mercury intrusion method. An ion exchange resin characterized in that the pore radius is 0.1 μm or more and the turbidity component eluted in the shaking turbidity test of the ion exchange resin is 45 ppm or less.
[2] The ion exchange resin according to [1], wherein the pore volume when measured by a mercury intrusion method is 0.20 mL / mL or more per volume in a water-wet state.
[3] The ion exchange resin according to [1] or [2], wherein the specific surface area is 5 m ² / g or more per 1 g of dry weight of the ion exchange resin.
[4] The ion exchange resin according to any one of [1] to [3], wherein the ion exchange capacity is 0.01 meq / mL or more and 0.4 meq / mL or less.
[5] A macroporous ion exchange resin having an ion exchange capacity of 0.4 meq / mL or less, and a pore volume measured by mercury porosimetry is 1 by the dry weight of the ion exchange resin.
An ion exchange resin characterized by being 0.1 mL / g or more per g.
[6] The specific surface area is 5 m ² / g or more per gram dry weight of the ion exchange resin, and the average pore radius when measured by a mercury intrusion method is 0.1 μm or more and 1 μm or less, Ion exchange resin.
[7] The ion exchange resin according to any one of [1] to [6], wherein the weight average particle size is 0.7 mm or less.
[8] The ion exchange resin according to any one of [1] to [7], wherein the uniformity coefficient is 1.2 or more.
[9] The ion exchange resin according to any one of [1] to [8], wherein an apparent density measured by a BSD method is 650 g / L or less.
[10] A method for producing a macroporous ion exchange resin, comprising the following steps (A) and (B):
(A) When copolymerizing a mixture of a monovinyl aromatic monomer and a crosslinkable aromatic monomer, a porosifying agent is added in an amount of 100% by weight or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. To obtain a crosslinked copolymer.
(B) A step of introducing an exchange group into the cross-linked copolymer obtained in (A) so that an ion exchange group introduction rate is 70% or less.
[11] A method for producing a macroporous anion exchange resin, comprising the following steps (a) to (c):
(A) When copolymerizing a mixture of a monovinyl aromatic monomer and a crosslinkable aromatic monomer, a porosifying agent is added in an amount of 100% by weight or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. To obtain a crosslinked copolymer.
(B) A step of haloalkylating the crosslinked copolymer obtained in (a) so that the haloalkyl group introduction rate is 70% or less.
(C) A step of reacting the haloalkylated crosslinked copolymer obtained in (b) with an amine compound.
[12] In (a), the addition amount of the porosifying agent is 105% by weight or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer, and in (b), the haloalkyl group The method for producing a macroporous anion exchange resin according to [11], wherein the introduction rate is 50% or less.
[13] A method for producing a macroporous anion exchange resin, comprising the following steps (a ′) to (d ′):
(A ′) When copolymerizing a monovinyl aromatic monomer and a crosslinkable aromatic monomer, a porosifying agent is added in an amount of 80% or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. Step of obtaining a polymer
(D ′) a step of setting the content of the eluting compound represented by the following formula (I) to 1000 μg or less with respect to 1 g of the monovinyl aromatic monomer and the crosslinkable aromatic monomer crosslinked copolymer.

(In the formula (I), Z represents a hydrogen atom or an alkyl group. L represents a natural number.)
(B ′) A step of haloalkylating the crosslinked copolymer obtained by reducing the eluting compound obtained in (d ′) at a haloalkyl group introduction rate of 85% or less.
A step of reacting the haloalkylated crosslinked copolymer obtained in (c ′) with an amine compound.
[14] A desalting apparatus, which is formed using the ion exchange resin according to any one of [1] to [9].
[15] A condensate demineralizer for power plants, formed using the ion exchange resin according to any one of [1] to [9].
[16] A method for removing a suspended metal corrosion product, comprising using the ion exchange resin according to any one of [1] to [9].

According to the present invention, it is possible to provide an ion exchange resin that is excellent in the removal performance of suspended metal corrosion products including clad and colloidal fine particles, has little elution, and has high mechanical strength.
Furthermore, since the ion exchange resin of the present invention has a large amount of adsorption to both the clad and the colloidal fine particles, the desalination apparatus filled with the ion exchange apparatus of the present invention can improve the purity of the treated water. Furthermore, the processing capacity per unit time can be improved. In addition, since the frequency of regeneration and replacement of the ion exchange resin that has broken through adsorption can be reduced, productivity can be improved and the amount of radioactive waste can be reduced.

It is the graph which showed the time-dependent change of DF value in a suspension metal corrosion product removal test. It is a SEM and EPMA image of the surface of the ion exchange resin of Example 1 after a fine particle removal test. It is a graph which shows the relationship between the linear velocity and pressure loss (MPa / m-bed) in the mixed bed ion exchange resin (expected model) using Example 2 and Example 2, and a reference example.

Hereinafter, embodiments of the present invention will be described in detail. In addition, the following description is an example of the embodiment of this invention, Comprising: This invention is not limited to the following description, unless the summary is exceeded.
[1] Ion exchange resin
The ion exchange resin of the present invention is a macroporous type, and the pore volume when measured by a mercury intrusion method is 0.5 mL / g or more per 1 g of the dry weight of the ion exchange resin, and measured by the mercury intrusion method. In this case, the pore radius is 0.1 μm or more, and the turbidity component eluted in the shaking turbidity test of the ion exchange resin is 45 ppm or less. Moreover, it is preferable here that the pore volume when measured by the mercury intrusion method is 0.20 mL / mL or more per volume in a water-wet state (the ion exchange resin of the first invention).

Further, the ion exchange resin of the present invention is a macroporous ion exchange resin, the exchange capacity of the ion exchange resin is 0.4 meq / mL or less, and mercury per 1 g of the ion exchange resin at the time of drying. The pore volume as measured by the press-fitting method may be 0.1 mL / g or more (the ion exchange resin of the second invention).
Furthermore, the specific surface area when measured by the mercury intrusion method is 5 m ² / g or more per gram dry weight of the ion exchange resin, and the average pore radius when measured by the mercury intrusion method is 0.1 μm or more and 1 μm. It may be characterized by the following (the ion exchange resin of the third invention).

Hereinafter, the ion exchange resin of the first invention, the ion exchange resin of the second invention, and the ion exchange resin of the third invention will be collectively referred to as the ion exchange resin of the present invention. Will be explained as a common matter.
Since it is preferable that it is an anion exchange resin as an ion exchange resin of this invention, the case where it is an anion exchange resin is demonstrated as a typical example hereafter.

However, the present invention is applicable not only to anion exchange resins but also to general ion exchange resins including cation exchange resins and chelate resins. This is because an anion exchange group or a cation exchange group may be selected according to the substance to be adsorbed or the zeta potential of the colloidal fine particles.
In addition, it is known that the adsorption mechanism of colloidal microparticles is adsorption by a zeta potential difference. Since an anion exchange resin has a positive zeta potential, it is suitable for adsorption of a substance having a negative zeta potential. On the other hand, since the cation exchange resin has a negative zeta potential, it is suitable for adsorption of a substance having a positive zeta potential. A chelating group can also be used because it has a zeta potential. That is, any functional group may be selected as long as it has a zeta potential.

The ion exchange resin of the present invention can adsorb not only clad and colloidal suspended metal corrosion products but also general colloidal fine particles.
Examples of the colloidal fine particles that can be adsorbed on the ion exchange resin of the present invention include metal oxides such as cobalt, chromium, manganese, iron, nickel, insoluble and hardly soluble salts of metals, and radioisotopes of the above metals. Of these substances. For example, iron oxide, magnetite (Fe3O4), nickel oxide, cobalt oxide, chromium oxide, manganese oxide and the like can be mentioned. Examples of colloidal fine particles of general metal species that can be adsorbed other than the above include colloidal fine particles of silica, colloid of aluminum hydroxide, and the like.

Further, the agglomerated colloid contained in the water treated with the aggregating agent in the tap water production process can also be adsorbed by the ion exchange resin of the present invention. In addition, biologically relevant polymer substances such as colloidal substances contained in blood and plasma, proteins, monosaccharides, polysaccharides, antibodies, nucleic acids, amino acids, fatty acids, fatty acid esters, and the like are also used in the ion exchange resin of the present invention. It can be adsorbed with.
[1-1] Pore radius
Here, the macroporous type generally refers to those having huge pores, and the average pore radius is usually 800 mm (0.08 μm) or more, preferably 1000 mm (0.1 μm) or more. Usually, the macroporous type has a large pore radius that usually exceeds 1 μm. That is, from the viewpoint of removing the clad, a structure in which the clad is taken into the giant pores is considered to be important, and a resin structure having an average pore radius that greatly exceeds the particle diameter of the clad has been designed. However, the present inventors have found that such a macroporous structure having pores having a relatively small radius that does not exceed 1 μm can effectively remove the clad. This is presumed to be because the pores having a relatively large radius can be sufficiently adsorbed on the surface of the anion exchange resin, and the adsorption area can be sufficiently secured, even if the clad is not incorporated into the giant pore diameter. . That is, the anion exchange resin of the present invention has an average pore radius of usually 0.1 μm or more, preferably 0.2 μm or more, more preferably 0.5 μm or more, and usually 10 μm or less, preferably 5 μm or less, more preferably Is 2 μm or less, more preferably 0.8 μm or less, and even more preferably 0.6 μm or less.

When the average pore radius of the ion exchange resin of the present invention is 1 μm or more, the pore volume in a water-wet state can be adjusted by adjusting the ion exchange capacity, the addition amount of a porosifying agent described later, and the like. It is preferable to adjust so that it may become large.
In addition, a porous crosslinked polymer in which large pores and small pores coexist as described in JP-A-2004-190014 can be preferably used as the precursor of the ion exchange resin of the present invention. In this case, an ion exchange resin in which large pores and small pores coexist can be formed.

Further, from the relationship between the pores and the surface area, the specific surface area of the pores of the ion exchange resin when measured by a mercury intrusion method is 2 m ² / g or more per 1 g of the dry weight of the anion exchange resin, and An anion exchange resin having an average pore radius of 0.1 μm or more and 1 μm or less as measured by a mercury intrusion method is more preferable. The specific surface area of the pores of the ion exchange resin is usually 2 m ² / g or more, preferably 3 m ² / g or more, more preferably 5 m ² / g or more, and further preferably 7 m ² / g or more. Moreover, it is 1000 m < ² > / g or less normally, Preferably it is 500 m < ² > / g or less, More preferably, it is 250 m < ² > / g.

When the specific surface area is too large, fine pores tend to increase, so that it is good for adsorption of fine substances, but tends to be disadvantageous for adsorption of large substances. On the other hand, if the specific surface area is too small, the surface area effective for adsorption decreases and the amount of adsorption tends to decrease.
By setting such a relatively small average pore radius, the strength of the anion exchange resin is increased, and crushing during handling and crushing during pumping of the resin slurry are suppressed. In addition, when the specific surface area is within the above range, the area to which the colloidal fine particles can be attached is increased, so that the capturing ability of the colloidal fine particles is also improved.

The average pore radius can be measured by a mercury intrusion method, that is, using a mercury porosimeter. In a mercury porosimeter, pressure is applied to mercury that has a large surface tension and does not react with most substances, and is pressed into the pores of a vacuum-dried sample (in the present invention, a gas adsorbent). Measure the volume of mercury intruded into the water.
In general, the relationship between the pressure when pressure is applied to enter the pores of the anion exchange resin and the pore diameter at which mercury can enter at the pressure is expressed by the Washburn formula as shown in the following calculation formula 1.
Formula 1:
Pr = -2σ cos θ
In the above calculation formula 1, P is pressure, r is pore radius, σ is surface tension of mercury, usually about 480 dyne / cm, and θ is contact angle between mercury and pore wall surface, usually about 140 °.

From the pressure and the amount of mercury that has entered the sample pores, the average pore radius can be calculated based on the above calculation formula 1, assuming that the pores are cylindrical.
Specific examples of measurement methods are shown below.
<Method of measuring pore properties>
A vacuum-dried resin (anion exchange resin) is placed in a glass cell, and the pore radius and pore volume of the resin are measured with a mercury porosimeter. Based on the histogram showing the distribution of the pores with the pore volume and pore radius as the vertical axis and the horizontal axis, respectively, the pore radius of the portion with the largest total pore volume is defined as the average pore radius.

The specific surface area can be measured as follows.
<Measurement method of specific surface area>
A known specific surface area measurement method can be applied. Using the resin obtained by drying, the specific surface area per dry weight of the resin is measured with a specific surface area meter (Flowsorb 2300, manufactured by Shimadzu Corporation). Further, the distribution of specific surface area is measured with a nitrogen adsorption meter (ASAP2400 manufactured by Micromeritics).

[1-2] Ion exchange capacity
As described above, a general anion exchange resin tends to be selected with a large ion exchange capacity from the viewpoint of incorporating a large amount of suspended metal corrosion products. The present inventor has found that the ion exchange capacity only needs to have an affinity with water to be desalted. Furthermore, it discovered that the eluate derived from anion exchange resin reduced by this, and the mixed bed resin layer of a desalting tower could be contaminated and the fall of water quality could also be suppressed.

That is, the anion exchange resin of the present invention has an ion exchange capacity per volume of usually 1.05 m.
eq / mL or less, preferably 0.4 meq / mL or less, more preferably 0.35 meq / mL or less, and usually 0.01 meq / mL or more, preferably 0.1 meq / mL or more.
[Measurement method of ion exchange capacity per volume]
Take 10 mL of OH-type anion exchange resin, pack it in a column, and pass 5% by weight aqueous NaCl solution 25 times the amount of resin, and collect all the effluent. The effluent is titrated with hydrochloric acid to calculate the exchange capacity (meq / mL).
The anion exchange resin of the present invention has an ion exchange capacity per dry weight of generally 4.4 meq / g or less, preferably 3.0 meq / g or less, more preferably 2.8 meq / g or less, and even more preferably 2.6 meq. / G or less, particularly preferably 2.0 meq / g or less, and usually 0.01 meq / g or more, preferably 0.1 meq / g or more, more preferably 0.5 meq / g or more, still more preferably 1. It is 0 meq / g or more, particularly preferably 1.6 meq / g or more.

[Measurement method of ion exchange capacity per dry weight]
The exchange capacity per dry weight of the OH type anion exchange resin is the ion exchange capacity per volume (meq / mL) measured in the above [Method for measuring ion exchange capacity per volume], and the following OH type anion exchange resin The ion exchange capacity per dry weight (meq / g) is calculated by the following formula using the water content of the slag and the apparent density measured by the [2-5] BSD method described later. The water content of the OH-type anion exchange resin in the following formula is determined by centrifuging the OH-type anion exchange resin to remove the attached water, and then using a digital automatic titrator (Mitsubishi Chemical Corporation (Fischer KF07 type equivalent) can be used.
<Calculation formula>
(Meq / g) = (meq / mL) × 1000 / apparent density × 100 / (100-water content (%))
In addition, as a method for setting the ion exchange capacity within the above range, a method for adjusting the degree of crosslinking, a method for adjusting the amount of the porous agent, and an exchange group introduction reaction such as a haloalkylation reaction and a sulfonation reaction described later are adjusted. And a method of adjusting by removing an exchange group.

[1-3] Pore volume
The anion exchange resin of the present invention has a pore volume per 1 g of the anion exchange resin in a dry state as measured by a mercury intrusion method, usually 0.1 mL or more, preferably 0.50 mL or more, more preferably 0.90 mL. As mentioned above, More preferably, it is 1.50 mL or more, Usually, 5.0 mL or less, Preferably it is 2.0 mL or less, More preferably, it is 1.6 mL or less.
Further, the anion exchange resin of the present invention has a pore volume converted to a water wet state of usually 0.20 mL or more, preferably 0.22 mL or more, more preferably 0.30 mL or more per 1 mL of the anion exchange resin. In addition, it is usually 5.0 mL or less, preferably 2.0 mL or less, more preferably 1.0 mL or less.
When the pore volume is in the above range, the colloidal fine particles captured by the ion exchange resin are easily diffused in the ion exchange resin particles, which tends to improve the capturing ability of the colloidal fine particles. In addition, since such ion exchange resins tend to improve the capture speed of colloidal fine particles, it is possible to increase the flow rate when passing through the column, and the flow processing capacity (productivity) tends to be improved. And preferred.

Examples of the method for setting the pore volume in the above range include a method for adjusting the amount of the porous agent.
In addition, the mercury intrusion method can be measured using a mercury porosimeter, similarly to the measurement of the average pore radius of [1-1].
In addition, the pore volume per 1 mL of the resin volume in the water wet state is the degree of swelling per 1 g of the dry resin (the dry volume of the pore volume measured by the mercury intrusion method per 1 g of the anion exchange resin in the dry state). It can be calculated by dividing by the resin volume in a water-swelled state per 1 g of resin (see the following calculation formula).

<Calculation formula>
(Pore volume per 1 mL of resin volume in water wet state (unit mL / mL))
= (Pore volume per 1 g of dried resin (unit mL / g)) / (swelling degree per 1 g of dried resin (unit mL / g))
Here, in the above calculation formula, the degree of swelling is a dry weight (Y (unit: g)) when a water-wet resin having a fixed volume (for example, 10 mL) (Z (unit: mL)) is dried. Can be obtained by measuring (see [1-8] degree of swelling described later).

[1-4] Weight average particle diameter
As described above, general anion exchange resins tend to be selected from those having large pores from the viewpoint of incorporating a large amount of suspended metal corrosion products. Therefore, anion exchange resins having a relatively large weight average particle diameter tend to be used. The present inventor has found that the cladding removal effect can be obtained by the filter effect by making the weight average particle diameter smaller than that of the conventional anion exchange resin and by reducing the gap between the respective anion exchange resin particles.

That is, the anion exchange resin of the present invention has a weight average particle size of usually 0.7 mm or less, preferably 0.6 mm or less, more preferably 0.55 mm or less, and further preferably 0.5 mm or less. Moreover, it is 0.01 mm or more normally, Preferably it is 0.1 mm or more, More preferably, it is 0.3 mm or more.
If the weight average particle size is too large, the ability to capture colloidal particles tends to decrease, and if it is too small, the ability to capture colloidal particles improves, but the pressure loss when passing through the column tends to increase.

The anion exchange resin of the present invention having a weight average particle diameter in the above range can be obtained by, for example, a known classification method. As the classification method, classification using a sieve, a water sieve using a water stream, a wind sieve using an air stream, and the like can be used.
The weight average particle diameter is measured by a known calculation method described on pages 139 to 141 of “Diaion I Fundamentals” 14th edition (September 1, 1999) issued by Ion Exchange Resin Division, Mitsubishi Chemical Corporation. Is done.

<Weight average particle size measurement method>
The sieves having a sieve mesh diameter of 1180 μm, 850 μm, 710 μm, 600 μm, 425 μm, and 300 μm are stacked so that the sieve mesh diameter decreases as it goes downward. The stacked sieve is placed on a vat, and about 100 mL of anion exchange resin is placed in the 1180 μm sieve stacked on the top.

Gently pour water onto the resin from a rubber tube connected to tap water and screen the small particles downward. The anion exchange resin remaining in the 1180 μm sieve is further screened for small particles by the following method. That is, water is filled up to a depth of about 1/2 of another bat, and a 1180 μm sieve is repeatedly shaken by giving up and down and rotational motion in the bat, and small particles are sieved.
The small particles in the vat are returned to the next 850 μm sieve, and the anion exchange resin remaining on the 1180 μm sieve is collected in another vat. If the sieve is clogged with anion exchange resin, place the sieve on the vat in reverse, closely contact with a rubber tube connected to tap water, and remove the clogged anion exchange resin by strongly flowing water. The extracted anion exchange resin is transferred to a vat from which the anion exchange resin remaining on the 1180 μm sieve is collected, and the volume is measured with a graduated cylinder. Let this volume be a (mL). The anion exchange resin that passed through the 1180 μm sieve was subjected to the same operation for each of the 850 μm, 710 μm, 600 μm, 425 μm, and 300 μm sieves, and the volume b (mL), c (mL), d (mL), e (mL) and f (mL) are obtained, and finally, the volume of the resin that has passed through the 300 μm sieve is measured with a graduated cylinder to be g (mL).

V = a + b + c + d + e + f + g, a / V × 100 = a ′ (%), b / V × 100 = b ′ (%), c / V × 100 = c ′ (%), d / V × 100 = d ′ ( %), E / V × 100 = e ′ (%), f / V × 100 = f ′ (%), g / V × 100 = g ′ (%).
From the above a ′ to g ′, the residual amount cumulative (%) of each sieve is taken on one axis, and the diameter (mm) of the sieve mesh is taken on the other axis, and this is plotted on the logarithmic probability paper. Take 3 points in the order of the remaining amount, draw a line that satisfies these 3 points as much as possible, obtain the diameter (mm) of the sieve mesh corresponding to 50% of the accumulated residue from this line, and calculate the weight average The particle size.

[1-5] Uniformity coefficient
There was a tendency that general ion exchange resins having a small uniformity coefficient, that is, having a uniform particle diameter are suitable. When the uniformity coefficient is larger than that of the conventional anion exchange resin, the present inventor will fill the gaps of the anion exchange resin particles having a large particle size with an anion exchange resin having a small particle size, and reduce the gaps between the particles. It was found that the clad can be efficiently removed by the filter effect.

The anion exchange resin of the present invention has a uniformity coefficient of 1.2 or more, preferably 1.25 or more, more preferably 1.3 or more, further preferably 1.35 or more, more preferably 1.6 or more, and more preferably 1. .7 or more. Moreover, it is 5 or less normally, Preferably it is 3 or less, More preferably, it is 2 or less.
The uniformity coefficient is measured by a known calculation method described on pages 139 to 141 of “Diaion I Fundamentals” 14th edition (September 1, 1999) published by Mitsubishi Chemical Corporation Ion Exchange Resin Division. .

  If the uniformity coefficient is small, the particle size uniformity increases, so there is an advantage that the pressure loss at the time of column packing is reduced. However, since there are no fine particles that fill the voids between the particles, the filter performance slightly decreases. There is a tendency. When the uniformity coefficient is large, the non-uniformity of the particle diameter increases, so that the pressure loss at the time of column packing tends to increase, but the filter performance tends to improve. Therefore, it is preferable to adjust the uniformity coefficient so as to obtain desired characteristics.

<Uniformity coefficient measurement method>
An anion exchange resin sieved by the above-mentioned weight average particle diameter measuring method is used. On the log-probability paper, plot the residual cumulative total (%) of each of the sieves a to g and the corresponding sieve diameter (mm), and select three points in descending order of residuals. Draw a straight line that satisfies as much as possible. From this straight line, the diameter (mm) of the sieve mesh corresponding to 90% of the accumulated residue is obtained, and this is set as the effective diameter. Next, the diameter (mm) of the sieve mesh corresponding to the residual amount of 40% is obtained, and the uniformity coefficient is obtained by the following equation.

Uniformity coefficient = [diameter of mesh corresponding to 40% cumulative residue (mm)] / [effective diameter (mm)
]
[1-6] Apparent density
The anion exchange resin of the present invention preferably has a relatively low apparent density for the purpose of reducing particle gaps and obtaining a cladding removal effect by a filter effect. That is, the anion exchange resin of the present invention has an apparent density of 650 g / L or less, preferably 640 g / L or less, more preferably 620 g, measured by a backwash water draining method (hereinafter sometimes referred to as “BSD method”). / L or less. Moreover, it is 500 g / L or more normally, Preferably it is 550 g / L or more, More preferably, it is 580 g / L or more.

The preferred range of the apparent density measured by the Tap method is usually 700 g / L or less, preferably 690 g / L or less, more preferably 670 g / L or less, and usually 550 g / L or more, preferably 600 g / L or more. More preferably, it is 630 g / L or more.
If the apparent density measured by the BSD method or the Tap method is too high, the filter effect tends to be weak, and if it is too low, the resin tends to float when packed in the column.

The apparent density is a known calculation method described in “Diaion I Fundamentals” 14th edition (September 1, 1999), pages 138 to 139, issued by Mitsubishi Chemical Corporation Ion Exchange Resin Division, Tap method, It is measured using a BSD method or the like.
It is.
<Apparent density measurement method>
5 mL of an anion exchange resin is taken using a graduated cylinder, its volume V (mL) is measured, and the weight W (g) of the anion exchange resin in a wet state after removing adhering moisture by centrifugation at 3000 rpm for 5 minutes. Is calculated by the following formula.
Apparent density (g / L) = W / V × 1000
<Tap method>
About 150 g of anion exchange resin is taken and the weight (g) of the sample is accurately weighed. Next, it was put into a 500 mL graduated cylinder with demineralized water, and the bottom was tapped until the volume did not decrease, and the volume V (mL) was read. The apparent density was calculated by the following formula.

Apparent density (g / L) = (Weighed sample weight) / V × 1000
<BSD method>
About 150 g of sample is taken and the weight (g) of the sample is accurately weighed. Transfer this to a measuring tube containing demineralized water in advance. Next, demineralized water is flowed from the bottom at a rate of 50 to 60% of bed expansion, and backwashing is performed until the resin surface is in equilibrium. Next, after stopping the desalted water and allowing to stand for 2 minutes, the water in the measuring tube is drawn from the bottom at a speed of LV = 9 to 15 m / hr until the water surface remains about 10 mm above the resin layer surface, and the resin after standing for 1 minute. The capacity is read, and the apparent density is obtained by the formula described in <Tap method> above.

[1-7] Elution amount
The anion exchange resin of the present invention has an impurity elution amount of 8 ppm or less, preferably 7 ppm or less, more preferably 6 ppm or less, as measured by the method described below. Moreover, it is 0.0001 ppm or more normally, Preferably it is 0.001 ppm or more, More preferably, it is 0.1 ppm or more.

If the amount of elution is too large, the ion exchange resin may capture the colloidal particles, and then the colloidal particles may leak together with the ion exchange resin eluate.
<Elution amount measurement method>
An amount equivalent to 10 mL of anion exchange resin is weighed into a flask, 0.1% aqueous hydrogen peroxide is added to 100 mL, and the flask is stoppered and shaken at 100 rpm for 20 hours in a thermostatic bath kept at 40 ° C. Thereafter, the supernatant water is collected, and the amount of elution (hereinafter sometimes referred to as “TOC”) is measured with a TOC measuring device (for example, a TOC measuring device “TOC5000A” manufactured by Shimadzu Corporation).

The elution amount can also be measured by the method described in JP-A-2006-328290, for example.
[1-8] Swelling degree The degree of swelling usually refers to the degree of swelling in water (water swelling degree). Swelling degree (water swelling degree) is a dry weight (Y (g)) measured when a water-wet resin having a certain amount (for example, 10 mL) of volume (Z (units mL)) is dried. And it can obtain | require by substituting into the following formulas.

<Calculation formula>
(Degree of swelling in water per gram of dry resin (unit: mL / g)
= (Volume of resin in wet state in water (Z (unit: mL)) / (dry weight when dried (Y (unit: g)))
The degree of swelling is used when the physical property value of pores measured in a dry state is converted to a value in a wet state. For example, the pore volume per 1 mL of the resin volume in a water-wet state is the pore volume per 1 g of the resin in the dry state by the swelling degree per 1 g of the dry resin (the resin volume in the water-swelled state per 1 g of the dry resin). It can be calculated by dividing.

Moreover, the specific surface area in the water-wet state can also be calculated by dividing the specific surface area per 1 g of the resin in the dry state by the swelling degree per 1 g of the dry resin.
Also, the pore radius in the water-wet state can be calculated by dividing the pore radius per 1 g of the resin in the dry state by the swelling degree per 1 g of the dry resin.
If the degree of swelling is too large, the pore property values (pore volume, specific surface area, pore radius) measured in the dry state are divided by the value of the degree of swelling and converted to the wet state. Since the physical property value contributes to a decreasing direction, it is preferable that the degree of swelling is not too high in order to keep the pore physical property value in a wet state large. On the other hand, when the degree of swelling is too small, the yield decreases in the production of the ion exchange resin, and the productivity tends to decrease.

The preferred range of the degree of swelling is usually 4.3 mL / g or more, preferably 4.5 mL / g or more, more preferably 4.7 mL / g or more, and usually 6 mL / g or less, preferably 5.7 mL / g, More preferably, it is 5.5 mL / g, More preferably, it is 4.7 mL / g, More preferably, it is 4.5 mL / g or less.
[1-9] True specific gravity
The ion exchange resin of the present invention preferably has a lower true specific gravity. An ion exchange resin having a low true specific gravity is preferable because the voids in the particles are large and a structure having good intra-particle diffusibility is obtained, and the capturing speed and amount of colloidal fine particles are increased. If the true specific gravity is too small, the specific gravity difference from the treatment liquid becomes small and tends to float in the liquid.

A known method is used as a method for adjusting the true specific gravity to be low. One example is to reduce the amount of exchange capacity introduced. It is also possible to adjust the true specific gravity by controlling the surface properties of the ion exchange resin particles.
When the ion exchange resin is used in water, the preferable range of the true specific gravity is usually 1.00 or more, preferably 1.01 or more, more preferably 1.02 or more, and usually 5.0 or less, preferably 2.0 or less, more preferably 1.05 or less. In addition, when using in liquids other than water, true specific gravity larger than the specific gravity of this liquid is preferable. The preferred true specific gravity in a liquid other than water is usually plus 0.01 or more, preferably plus 0.02 or more, and usually plus 4.0 or less, preferably plus 1.0 or less than the specific gravity of the liquid. More preferably, it is plus 0.05 or less.

In addition, it is preferable even if the true specific gravity of the ion exchange resin of this invention is lower than the specific gravity of the liquid to be used. In that case, since the ion exchange resin floats in the liquid, a known method such as a method of flowing in an upward flow can be used as a countermeasure.
<Measurement method of true specific gravity>
The dried pycnometer with thermometer is weighed (this weight is referred to as “Ag”).
Next, about 1/3 of the resin is put into a pycnometer and the whole weight is measured (this weight is referred to as “Bg”).

The pycnometer is filled with demineralized water and immersed in a thermostat set at 25 ° C. When the internal temperature reaches 25 ° C., water is drawn out to the marked line with a syringe, stoppered, taken out from the thermostatic bath, wiped off the water outside the pycnometer, and weighed (this weight is referred to as “Cg”).
Next, the resin and demineralized water of the pycnometer are extracted, and only demineralized water is added and immersed in a thermostatic bath. When the temperature reaches 25 ° C., the water is drawn to the marked line with a syringe, stoppered, and taken out from the thermostatic bath. The moisture outside the pycnometer is wiped off and weighed (this weight is hereinafter referred to as “Dg”).

The true specific gravity can be calculated by the following equation.
True specific gravity = (B−A) × DW / ((D−A) + (B−A) − (C−A))
DW: Demineralized water density at 25 ° C
[1-8] Suspension metal corrosion product removal effect
In the anion exchange resin of the present invention, the DF value of the suspending metal corrosion product measured by the following suspending metal corrosion product removal test is 2 or more, preferably 10 or more 90 minutes after the start of liquid flow, More preferably, it is 20 or more. Moreover, it is 1000 or less normally, Preferably it is 500 or less, More preferably, it is 400 or less.

The DF value is obtained by dividing the concentration of the substance to be removed at the inlet of the column by the concentration of the substance to be removed at the outlet of the column. The method described in the section of the following suspension metal corrosion product removal test is preferably used.
If the DF value is too small, the substance to be removed tends to leak from the column outlet without being removed from the column inlet to the outlet. If the DF value is too large, the concentration of the removal target substance at the column inlet may be too high.

<Suspension metal corrosion product removal test>
An anion exchange resin is packed into a column with an inner diameter of 20 mm so that the packing height is 200 mm, and magnetite (Fe 3 O 4) particles (for example, manufactured by High Purity Chemical Laboratory Co., Ltd., average diameter 1.4 μm, distribution 0.5 to 3 μm). ) Is dispersed at a flow rate of 300 mL / min. Water at the column inlet and outlet is collected every predetermined time after the start of water flow, aqua regia is added to dissolve the magnetite, and the iron concentration is quantified by ICP-MS method.

The DF value is calculated by the following formula.
DF = Fe concentration at the column inlet / Fe concentration at the column outlet
[1-9] Strength
As described above, the anion exchange resin of the present invention has high mechanical strength, reduces fine particles and turbidity / eluate due to the fragment of the anion exchange resin, and is less contaminated with the mixed bed resin layer of the desalting tower, High-purity condensate desalination can be performed.

The strength of the ion exchange resin can be evaluated by the turbidity measured by the following turbidity test after shaking. This method of turbidity test after shaking is to measure the turbidity of the supernatant water after shaking the ion exchange resin soaked in water for a certain period of time. The smaller the turbidity measured by this method, the greater the strength of the ion exchange resin.
That is, the anion exchange resin of the present invention has a turbidity measured by the following shaking turbidity test of usually 1,000 ppm or less, preferably 150 ppm or less, more preferably 100 ppm or less, particularly preferably 50 ppm or less, particularly preferably. 45 ppm or less, particularly preferably 15 ppm or less. Moreover, it is 0.0001 ppm or more normally, Preferably it is 0.001 ppm or more, More preferably, it is 0.01 ppm or more.

The salt form of the resin for measuring turbidity is measured according to the actual use conditions of the resin. For example, the anion exchange resin of the present invention is in the OH form.
Moreover, the intensity | strength of an ion exchange resin can be measured as follows.
<Turbidity removal test after shaking>
Weigh the equivalent of 10 mL of ion exchange resin into a flask, add ultrapure water to 100 mL, cap and shake at 100 rpm for 20 hours in a thermostatic bath kept at 40 ° C. Thereafter, supernatant water is collected, and turbidity (ppm) is measured with an integrating sphere turbidity measuring device (for example, an integrating sphere turbidity measuring device manufactured by Mitsubishi Chemical).

[1-10] Pressure loss One of the hydraulic properties of the ion exchange resin is pressure loss. The pressure loss is the difference in pressure between the tower inlet and the tower outlet when passing through the ion exchange resin tower, and is known to be inversely proportional to the square of the particle size (Mitsubishi Chemical Corporation ion exchange resin). Issued by Division, “Diaion I Fundamentals”, 14th edition (September 1, 1999, p. 45).

The anion exchange resin of the present invention has a larger pressure loss than the conventional ion exchange resin when compared with the same particle size, the same flow rate, and the same layer height. As the pressure loss increases, the filter medium resistance of the resin layer increases, so that the collection performance of the colloidal particles to be removed tends to increase.
That is, the anion exchange resin of the present invention has a pressure loss measured in the following pressure loss test, which is a conventional ion exchange resin (gel ion exchange resin, for example, mixed bed ion exchange resin (registered trademark) Diaion SMN1). Is usually 1.05 times or more, preferably 1.1 times or more, more preferably 1.5 times or more. The upper limit of the pressure loss is usually 10 times or less, preferably 5 times or less, more preferably 3 times or less.

  Although the pressure loss of the ion exchange resin layer of the present invention is larger than before and the liquid flow resistance is increased, it is usually within the allowable range in the design of the existing ion exchange resin tower and is not particularly problematic. . For example, in applications such as those described in [4-1], which will be described later, since a part of the existing mixed bed ion exchange resin layer is replaced with the anion exchange resin of the present invention and laminated, the pressure loss is the existing ion exchange. It is also possible to determine the lamination ratio of the anion exchange resin of the present invention so as to be within the allowable range of the resin tower.

The pressure loss can be measured as follows.
<Pressure loss measurement method>
A jacketed glass column with a diameter of 20 mm is filled with an amount equivalent to 157 mL of ion exchange resin, the liquid is passed in a downward flow, and the pressure at the inlet and outlet of the column is measured. The pressure loss is calculated by converting the pressure difference between the column inlet and the outlet per 1 m of layer height of the ion exchange resin, as in the following equation.
Pressure loss (MPa / m-bed) = (Column inlet pressure-Column outlet pressure) / (Layer height of ion exchange resin)
[1-11] Adsorption zone When the colloid particle suspension is passed through the ion exchange resin column, the colloid particles are captured from the upper layer of the column to form an adsorption zone. The capturing ability of colloidal particles means that the adsorption band is long and weak. On the contrary, if the adsorption zone is short, it means that the capturing ability of the colloidal particles is good.

Since the ion exchange resin of the present invention is excellent in the ability to capture colloidal particles, the adsorption zone of the colloidal particles is short and is effectively captured at the upper layer of the column.
The adsorption band can be measured as follows.
<Adsorption zone evaluation method>
Evaluation can be made by collecting the liquid from sampling ports provided at the upper, middle and lower portions of the ion exchange resin and measuring the colloidal particle concentration in the column.

  An anion exchange resin is packed into a column with an inner diameter of 20 mm so that the packing height is 200 mm, and magnetite (Fe 3 O 4) particles (for example, manufactured by High Purity Chemical Laboratory Co., Ltd., average diameter 1.4 μm, distribution 0.5 to 3 μm). ) Is dispersed at a flow rate of 300 mL / min. The water at the column inlet, the center of the column, and the column outlet 90 minutes after the start of water flow is collected, aqua regia is added to dissolve the magnetite, and the iron concentration is quantified by ICP-MS method.

[1-12] Particle size distribution The particle size distribution is measured by using the result obtained by the weight average particle size measurement method described above. The particle size ratio is 420 to 1190 μm (16 to 40 mesh), the ratio is 420 μm or less, and 1190 μm. Each of the above ratios is calculated by interpolation.
In the ion exchange resin of the present invention, the ratio of 420 μm or less is usually 10% or less, preferably 5% or less, more preferably 1% or less. The ratio of 1190 μm or more is usually 10% or less, preferably 5% or less, and more preferably 1% or less.

The anion exchange resin of the present invention having the above particle size distribution can be obtained by, for example, a known classification method. As the classification method, classification using a sieve, a water sieve using a water stream, a wind sieve using an air stream, and the like can be used.
Increasing the proportion of small particles tends to improve the performance of removing colloidal fine particles, but tends to increase the pressure loss when packed in a column. On the other hand, when the ratio of large particles increases, the removal performance of colloidal particles tends to decrease, but the pressure loss when packed in a column tends to decrease. Therefore, it is preferable to appropriately adjust the particle size distribution so that the desired characteristics can be obtained according to the application.

[1-13] SEM and EPMA image observation SEM / EPMA image observation is performed after the suspension metal corrosion product removal test described in [1-8] Suspension metal corrosion product removal effect is performed. The exchange resin is taken out of the column, and the surface is observed with SEM and EPMA to observe the adhesion state of the magnetite particles.
The anion exchange resin of the present invention is characterized in that, in SEM and EPMA image observation, the thinned magnetite particles enter into the concave portion of the resin surface, and are observed in a collective state in which the particles are connected to each other through the entering particles. .

[2] Method for producing anion exchange resin When the first ion exchange resin of the present invention is an anion exchange resin, it comprises the following steps (a) to (c): It may be referred to as “1. Manufacturing method of the present invention”).
(A) When copolymerizing a mixture of a monovinyl aromatic monomer and a crosslinkable aromatic monomer, a porosifying agent is added in an amount of 100% by weight or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. To obtain a crosslinked copolymer.
(B) A step of haloalkylating the crosslinked copolymer obtained in (a) so that the haloalkyl group introduction rate is 70% or less.
(C) A step of reacting the haloalkylated crosslinked copolymer obtained in (b) with an amine compound.

In addition, in (a), the addition amount of the porosifying agent is 105% by weight or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer, and in (b), a haloalkyl group is introduced. When the ratio is 50% or less, there is an advantage that a porous crosslinked polymer having a large pore volume can be obtained in the copolymerization of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. In addition, the introduction of the haloalkyl group is preferable because the haloalkyl group tends to be introduced while maintaining a large pore volume and ensuring the resin strength.

Moreover, you may have the following process (d) between the (a) process and the (b) process as needed.
(D) A step of setting the content of the eluting compound represented by the following formula (I) to 1000 μg or less with respect to 1 g of the monovinyl aromatic monomer and the crosslinkable aromatic monomer crosslinked copolymer.

(In the formula (I), Z represents a hydrogen atom or an alkyl group. L represents a natural number.)
Moreover, you may have the following (e) process between the (b) process and the (c) process as needed.
(E) A step of removing the eluting compound represented by the following formula (II) from the haloalkylated crosslinked copolymer

(In formula (II), X represents a hydrogen atom, a halogen atom, or an alkyl group which may be substituted with a halogen atom. Y represents a halogen atom. M and n each independently represent a natural number. )
In the case where the ion exchange resins of the second and third inventions are anion exchange resins, the method includes the following steps (a ′) to (d ′) (hereinafter referred to as “second”). It may be referred to as “the production method of the present invention”).
(A ′) When copolymerizing a monovinyl aromatic monomer and a crosslinkable aromatic monomer, a porosifying agent is added in an amount of 80% or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. Step of obtaining a polymer
(D ′) a step of setting the content of the eluting compound represented by the following formula (I) to 1000 μg or less with respect to 1 g of the monovinyl aromatic monomer and the crosslinkable aromatic monomer crosslinked copolymer.

(In the formula (I), Z represents a hydrogen atom or an alkyl group. L represents a natural number.)
(B ′) A step of haloalkylating the crosslinked copolymer obtained by reducing the eluting compound obtained in (d ′) at a haloalkyl group introduction rate of 85% or less.
A step of reacting the haloalkylated crosslinked copolymer obtained in (c ′) with an amine compound.
Hereinafter, the manufacturing method of the first invention and the manufacturing method of the second invention will be collectively referred to as the manufacturing method of the invention, and the contents of the common steps will be described as common matters. That is, the steps (a) and (a ′) are the steps (a), the steps (b) and (b ′) are the steps (b), the steps (c) and (c ′) are the steps (c), The steps (d) and (d ′) will be described as step (d), and common items will be described together.

[2-1] (a) Step of obtaining a cross-linked copolymer by copolymerizing a monovinyl aromatic monomer and a cross-linkable aromatic monomer
Examples of the monovinyl aromatic monomer according to the present invention include alkyl-substituted styrenes such as styrene, methylstyrene, and ethylstyrene, and halogen-substituted styrenes such as bromostyrene. These may be used alone or in combination of two or more. Among these, styrene or a monomer mainly composed of styrene is preferable.

  Cross-linkable aromatic monomers include divinylbenzene, trivinylbenzene, divinyltoluene, divinylnaphthalene, divinylxylene, divinylbiphenyl, bis (vinylphenyl) methane, bis (vinylphenyl) ethane, bis (vinylphenyl) propane, bis And (vinylphenyl) butane. These may be used alone or in combination of two or more. Of these, divinylbenzene is preferred.

Industrially produced divinylbenzene usually contains a large amount of by-product ethyl vinylbenzene (ethyl styrene), but such divinylbenzene can also be used in the present invention.
The amount of the crosslinkable aromatic monomer used is usually 0.5 to 30% by weight, preferably 2.5 to 12% by weight, more preferably 4 to 10% by weight, based on the total monomer weight. As the amount of the crosslinkable aromatic monomer used increases and the degree of crosslinking increases, the oxidation resistance of the resulting anion exchange resin tends to improve. On the other hand, when the degree of crosslinking is too high, the leaching oligomers are easily removed by water washing in the subsequent step. In addition, in the latter stage (b) haloalkylation step, when the step of reducing the conversion rate of haloalkylation is carried out, the post-crosslinking reaction as a side reaction of haloalkylation is also suppressed. A method of increasing the addition amount of the crosslinkable aromatic monomer is also preferably used.

The copolymerization reaction of the monovinyl aromatic monomer and the crosslinkable aromatic monomer can be performed based on a known technique using a radical polymerization initiator.
As the radical polymerization initiator, one kind or two or more kinds such as dibenzoyl peroxide, lauroyl peroxide, t-butyl hydroperoxide, azobisisobutyronitrile are used. It is used in a range of 05% by weight to 5% by weight.

The polymerization mode is not particularly limited, and the polymerization can be carried out in various modes such as solution polymerization, emulsion polymerization, suspension polymerization, etc. Among them, suspension in which a uniform bead-shaped copolymer can be obtained. A polymerization method is preferably employed. The suspension polymerization method can be carried out by selecting a known reaction condition using a solvent, a dispersion stabilizer or the like generally used for the production of this type of copolymer.
The polymerization temperature in the copolymerization reaction is usually room temperature (about 18 ° C. to 25 ° C.) or more, preferably 40 ° C. or more, more preferably 70 ° C. or more, and usually 250 ° C. or less, preferably 150 ° C. or less. Preferably it is 140 degrees C or less. If the polymerization temperature is too high, depolymerization occurs at the same time, and the degree of polymerization completion is lowered. If the polymerization temperature is too low, the degree of polymerization completion will be insufficient.

The polymerization atmosphere can be carried out under air or under an inert gas, and nitrogen, carbon dioxide, argon or the like can be used as the inert gas.
Moreover, the polymerization method described in JP-A-2006-328290 can also be suitably used.
Moreover, the well-known method of obtaining the crosslinked copolymer of a uniform particle size can also be used conveniently.
For example, the methods disclosed in Japanese Patent Application Nos. 2000-219991, 2000-1111587, 57-102905, and 3-249931 can be preferably used.

The porosifying agent used in this step is a substance that dissolves in the monomer mixture but does not swell the copolymer (hereinafter sometimes referred to as “poor solvent”), or is dissolved in the monomer mixture. A substance that swells the copolymer (hereinafter sometimes referred to as “good solvent”) can be used.
Specifically, a water-insoluble organic compound can be used as the substance that dissolves in the monomer mixture but does not swell the copolymer. Examples of the water-insoluble organic compound include linear or branched hydrocarbons, linear or branched water-insoluble alcohols, polymers and copolymers. Examples of the linear or branched hydrocarbon include pentane, hexane, heptane, octane, nonane, decane, dodecane, isooctane, gasoline, mineral oil, toluene, benzene, xylene, diethylbenzene, and chlorobenzene. Examples of water-insoluble alcohols include alcohols having 4 or more carbon atoms and linear or branched alkyl chains, such as n-butanol, s-butanol, t-butanol, pentanol, hexanol, and octanol. And methyl isobutyl carbinol. Examples of the polymer include polystyrene, polyethylene, polypropylene, polyester, polyurethane and the like. Block copolymers can also be used.

As the porosifying agent, it is preferable to use methyl isobutyl carbinol or isooctane from the viewpoint of easy removal after the polymerization is completed or from the viewpoint of cost. In the case of the present invention, use of isooctane or heptane, which is a solvent that does not dissolve polystyrene (poor solvent), is convenient for target pore formation.
In addition, the amount of addition when a poor solvent is used as a porous agent is usually about 75% with respect to a polymerizable monomer (such as styrene or divinylbenzene) in the production of conventional porous ion exchange resins. It was. On the other hand, in the anion exchange resin of the present invention, a graft-modified polyvinyl alcohol (PVA) used in the polymerization of vinyl acetate or the like is used as a dispersion stabilizer during polymerization, and a larger amount of a porosifying agent can be added. I found. Since such graft-modified PVA has a functional group that is graft-bonded to the surface of the monomer, it has a high ability to protect monomer droplets during polymerization, and therefore can be stably polymerized even if a large amount of a porous agent is added. Conceivable.

Specific examples of substances (good solvents) that dissolve in the monomer mixture and swell the copolymer include aromatic hydrocarbons, toluene, xylene (ortho, meta, para), benzene, and chlorobenzene. Any ring-substituted aromatic hydrocarbon such as dichlorobenzene, nitrobenzene, bromobenzene, aniline, ethylbenzene, diethylbenzene, etc. can be used. Further, halogenated hydrocarbons and solvents such as dichloromethane, chloroform, dichloroethane and the like can also be used. These can be used alone or as a mixture. When such a good solvent is added, pores having a large pore diameter can be formed by simultaneously adding a polymer. Examples of the polymer include polystyrene, polyethylene, polypropylene, polyester, polyurethane and the like. Block copolymers can also be used.

  That is, the porosifying agent is usually 80% or more, preferably 90% or more, more preferably 100% or more, more preferably 105%, based on the weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. It is added in an amount of not less than wt%, particularly preferably not less than 120 wt%, and usually not more than 300%, preferably not more than 200 wt%. If the amount of the porosifying agent is too small, the pore size, pore volume, and specific surface area will be small. If the amount of the porosifying agent is too large, the polymerizability will be lowered, the productivity will be lowered, and the cost will be increased. The pore size, pore volume, and specific surface area become too large.

[2-2] (d) A step of setting the content of the eluting compound having a specific structure to 1000 μg or less with respect to 1 g of the crosslinked copolymer.
The method for producing an anion exchange resin of the present invention includes, if necessary, the inclusion of the eluting compound represented by the following formula (I) before haloalkylation of the crosslinked copolymer obtained in [2-1]. It is preferable to include a step of adjusting the amount (hereinafter sometimes referred to as “eluting compound (I)”) to 1000 μg or less, preferably 500 μg or less, more preferably 100 μg or less with respect to 1 g of the crosslinked copolymer.

(In the formula (I), Z represents a hydrogen atom or an alkyl group. L represents a natural number.)
Here, the alkyl group of Z is a C1-C8 alkyl group normally, Preferably, they are a methyl group, an ethyl group, a propyl group, and a butyl group, More preferably, they are a methyl group and an ethyl group.
When the content of the eluting compound (I) in the cross-linked copolymer to be subjected to haloalkylation is too large, it is impossible to obtain an anion exchange resin with a small amount of the eluting substance in which the remaining of impurities and the generation of decomposition products are suppressed. . The content of the eluting compound (I) is preferably as small as possible, but the lower limit is usually about 50 μg.

  The eluting compound (I) according to the present invention is an unreacted or incomplete reaction product obtained when copolymerizing a monovinyl aromatic monomer and a crosslinkable aromatic monomer. This eluting compound (I) causes an ion exchange resin eluate at the time of product, and has a weight average molecular weight in terms of polystyrene of usually 200 or more, preferably 300 or more, and usually 1,000,000. 000 or less, preferably 100,000 or less. For example, in the case of a styrene resin, styrene dimer, styrene trimer, styrene oligomer, etc. are mentioned as low polymer components that are insufficiently polymerized, and linear polystyrene, polystyrene fine particles, etc. are mentioned as free polymer components. Moreover, as a by-product in the chain transfer reaction in the polymerization reaction, a low polymer component or a free polymer component to which a polymerization inhibitor contained in the monomer is bonded can be mentioned.

The content of the eluting compound (I) in the crosslinked copolymer can be determined, for example, by the same method as the elution amount measuring method described in [1-7].
The step (d) according to the present invention may be performed simultaneously with the step (a) by adjusting the polymerization conditions in the step (a). Further, after the polymerization, the resulting crosslinked copolymer is washed to remove the eluting compound (I), thereby obtaining a crosslinked copolymer with a reduced content of the eluting compound.

In the case of obtaining a cross-linked copolymer having a low content of the eluting compound by adjusting the polymerization conditions in the step (a), examples of the method for adjusting the polymerization conditions include the following.
[2-2-1] Adjustment of polymerization temperature
As described above, if the polymerization temperature in the copolymerization reaction in the present invention is too high, depolymerization occurs at the same time, and the degree of completion of polymerization is lowered. On the contrary, if the polymerization temperature is too low, the degree of completion of polymerization becomes insufficient, and the eluting compound A crosslinked copolymer with a low content cannot be obtained. Accordingly, the polymerization temperature of the monovinyl aromatic monomer and the crosslinkable aromatic monomer is room temperature (about 18 ° C. to 25 ° C.) or higher, preferably 40 ° C. or higher, more preferably 70 ° C. or higher and 250 ° C. or lower, preferably 150 ° C. or lower. More preferably, it is adjusted appropriately within a range of 140 ° C. or less.

[2-2-2] Addition of deoxygenated monomer
A deoxygenated monomer is one in which the oxygen concentration in the monomer is lower than the saturated oxygen concentration. Low polymer components (dimers, trimers, oligomers) that are insufficiently polymerized, free polymer components (linear polymers, polymer fine particles) ), And has a role to suppress the generation of by-products due to the polymerization reaction. For example, the saturated oxygen concentration of a normal styrenic monomer is about 5% to 10% by weight. In the present invention, a deoxygenated monomer having a saturated oxygen concentration of less than 5% by weight, particularly 3% by weight or less is used. Is preferred.

  Specific methods for preparing the deoxygenated monomer include a method of bubbling the monomer with an inert gas, a method of degassing the membrane, a method of circulating the inert gas in the upper gas phase of the monomer storage tank, and a column such as silica gel. The method of doing is mentioned. Alternatively, commercially available deoxygenated monomers can also be used. Among them, the method of bubbling the monomer with an inert gas is preferable, and in this case, the inert gas used is preferably nitrogen, carbon dioxide, or argon. The deoxygenated monomer is stored in an inert gas atmosphere.

  The addition amount of the deoxygenated monomer is usually 10% by weight or more, preferably 50% by weight or more, more preferably 80% by weight or more based on the total amount of the monomer mixture. If the amount of deoxygenated monomer is too small, low polymer components (dimers, trimers, oligomers) that are insufficiently polymerized, free polymer components (linear polymers, polymer fine particles), and by-products due to polymerization reactions are generated. Become more.

[2-2-3] Use of monomer from which polymerization inhibitor has been removed
By removing the polymerization inhibitor in the mixture of monovinyl aromatic monomer and crosslinkable aromatic monomer used in the polymerization, low polymer components (dimers, trimers, oligomers) that are insufficiently polymerized, free polymer components (line) Generation of by-products due to polymerization reaction, polymer fine particles), polymerization reaction, and the like, and a crosslinked copolymer having a low content of eluting compounds can be obtained.

[2-2-4] Use of a crosslinkable aromatic monomer with few impurities
Usually, in the crosslinkable aromatic monomer, for example, divinylbenzene, non-polymerizable impurities such as diethylbenzene are present, which causes the formation of the eluting compound (I). The group monomer is preferably one having a low impurity content.
As such a crosslinkable aromatic monomer having a low impurity content, it is preferable to select and use a specific grade such that the crosslinkable aromatic monomer content (purity) is 57% by weight or more. In addition, a crosslinkable aromatic monomer having a small impurity content can be obtained by removing impurities by, for example, distillation.

  The crosslinkable aromatic monomer content (purity) of the crosslinkable aromatic monomer used in the present invention is particularly preferably 60% by weight or more, more preferably 80% by weight or more, and is non-polymerizable in the crosslinkable aromatic monomer. The impurity content is usually 5% by weight or less, preferably 3% by weight or less, more preferably 1% by weight or less per monomer weight. If this impurity content is too high, it tends to cause a chain transfer reaction to impurities during polymerization, so the amount of eluting oligomer (polystyrene) remaining in the polymer after polymerization may increase, and the eluting compound content A small amount of a crosslinked copolymer cannot be obtained.

[2-2-5] Adjustment of use amount of crosslinkable aromatic monomer
As described above, the more the crosslinkable aromatic monomer used for copolymerization, the more the oxidation resistance of the resin tends to be improved. On the other hand, if the degree of crosslinking is too high, removal of the eluting oligomer in the subsequent step is incomplete. The amount of the crosslinkable aromatic monomer is usually 0.5 to 55% by weight, preferably 2.5 to 5%, based on the total monomer weight, because it is difficult to obtain a crosslinked copolymer with a low content of the eluting compound. It adjusts suitably in 40 weight%, More preferably in the range of 10-30 weight%.

Moreover, the following washing | cleaning processes are employable as a preferable example when performing the (d) process after the said (a) process.
[2-2-6] Step of washing the crosslinked copolymer
In the present invention, if necessary, the crosslinked copolymer produced from the monovinyl aromatic monomer and the crosslinkable aromatic monomer in the step (a) is used with a solvent before the later-described (b) haloalkylation step. The eluting compound (I) can be removed by washing.

This washing method can be carried out by a column method in which a crosslinked copolymer is packed in a column and a solvent is passed, or by a batch washing method.
The washing temperature is usually room temperature (20 ° C) or higher, preferably 30 ° C or higher, more preferably 50 ° C or higher, particularly preferably 90 ° C or higher, and usually 150 ° C or lower, preferably 130 ° C or lower, more preferably 120 ° C or lower. It is. If the washing temperature is too high, the cross-linked copolymer will be decomposed. If the washing temperature is too low, the washing efficiency is lowered.

The contact time with the solvent is usually 5 minutes or longer, preferably 1 hour or longer, more preferably 2 hours or longer, and usually 4 hours or shorter. If the contact time with the solvent is too short, the cleaning efficiency is lowered, and if the time is too long, the productivity is lowered.
Solvents used for washing include aliphatic hydrocarbons having 5 or more carbon atoms, such as pentane, hexane, and heptane; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, diethylbenzene, and the like; alcohols such as methanol, Ethanol, propanol, butanol, etc .; ketones such as acetone, methyl ethyl ketone, etc .; ethers such as dimethyl ether, diethyl ether, methylal, etc .; chlorinated solvents such as dichloromethane, chloroform, carbon tetrachloride, dichloroethane, trichloroethane, etc .; phenols such as Such as phenol, and the like. These may be used alone or in combination of two or more. Of these, benzene, toluene, xylene, acetone, diethyl ether, methylal, dichloromethane, chloroform, dichloroethane, and trichloroethane are preferable. Further, a method of mixing these solvents with water, raising the temperature, and washing in an azeotropic state can also be employed.

[2-3] (b) Step of haloalkylating the crosslinked copolymer
The crosslinked copolymer obtained through the steps of [2-1] and [2-2] is then reacted with a haloalkylating agent in a swollen state in the presence of a Friedel-Crafts reaction catalyst. Turn into.
In order to swell the crosslinked copolymer, a swelling solvent such as dichloroethane can be used. In the present invention, it is preferable to swell only with a haloalkylating agent in order to sufficiently promote halomethylation.

Examples of Friedel-Crafts reaction catalysts include Lewis acid catalysts such as zinc chloride, iron (III) chloride, tin (IV) chloride, and aluminum chloride. These catalysts may be used individually by 1 type, and may mix and use 2 or more types.
In order to make the haloalkylating agent act not only as a reaction reagent but also as a swelling solvent for the copolymer, it is preferable to use one having a high affinity with the copolymer, for example, chloromethyl methyl ether, methylene chloride, bis ( And halogen compounds such as chloromethyl) ether, polyvinyl chloride, bis (chloromethyl) benzene, etc., and these may be used alone or in combination of two or more, but more preferably. Is chloromethyl methyl ether. That is, the haloalkylation in the present invention is preferably chloromethylation.

  The haloalkyl group introduction rate in this step is 85% or less, preferably 80% or less, more preferably 70%, based on the theoretical halogen content when the monovinyl aromatic monomer is assumed to be haloalkylated at 100 mol%. Below, it is more preferably 50% or less, particularly preferably 45% or less. Increasing this haloalkyl group introduction rate (percentage of the proportion of halogen atoms introduced to the theoretical halogen content assuming that the monovinyl aromatic monomer was haloalkylated at 100 mol%) increases the cross-linking The main chain of the coalescence may break or the excessively introduced haloalkyl group may be released after the introduction, causing impurities, but by limiting the introduction rate of haloalkyl groups in this way, the generation of impurities It is possible to obtain an anion exchange resin with a small amount of eluate.

In the present invention, by suppressing the introduction amount of the haloalkyl group, side reactions in the haloalkylation step are also reduced, so that it is considered that an eluting oligomer is hardly generated. Moreover, it is thought that the by-product which generate | occur | produces will also reduce the substance which is hard to wash and remove in a post process compared with the conventional prescription. As a result, an anion exchange resin with a remarkably small amount of eluate can be obtained.
Hereinafter, a specific method for introducing a haloalkyl group will be described in detail.

The amount of the haloalkylating agent used is selected from a wide range depending on the degree of crosslinking of the crosslinked copolymer and other conditions, but is preferably an amount that at least sufficiently swells the crosslinked copolymer. 1 times or more, preferably 2 times or more, usually 50 times or less, preferably 20 times or less.
The amount of the Friedel-Crafts reaction catalyst used is usually 0.001 to 10 times, preferably 0.1 to 2 times, more preferably 0.2 to 2 times the weight of the cross-linked copolymer. It is.

  Examples of means for bringing the haloalkyl group introduction rate into the cross-linked copolymer within the above range include means for lowering the reaction temperature, using a catalyst having low activity, and reducing the amount of catalyst added. That is, the main factors affecting the reaction between the cross-linked copolymer and the haloalkylating agent include reaction temperature, activity (type) of Friedel-Crafts reaction catalyst and its addition amount, haloalkylating agent addition amount, and the like. Therefore, the haloalkyl group introduction rate can be controlled by adjusting these conditions.

The reaction temperature varies depending on the type of Friedel-Crafts reaction catalyst to be used, but it is usually 0 ° C. or higher and must be suppressed to 55 ° C. at maximum.
The preferred reaction temperature range varies depending on the haloalkylating agent and Friedel-Crafts reaction catalyst used. For example, when chloromethyl methyl ether is used as the haloalkylating agent and zinc chloride is used as the Friedel-Crafts reaction catalyst. The temperature is usually 30 ° C. or higher, preferably 35 ° C. or higher, and is usually 50 ° C. or lower, preferably 45 ° C. or lower. At this time, excessive introduction of the haloalkyl group can be suppressed by appropriately selecting the reaction time and the like.

  In the haloalkyl group introduction reaction, the post-crosslinking reaction also proceeds at the same time, and there is a meaning of securing the strength of the final product by the post-crosslinking reaction. The reaction time for haloalkylation is preferably 30 minutes or longer, more preferably 3 hours or longer, and even more preferably 5 hours or longer. Further, it is preferably 24 hours or less, more preferably 12 hours or less, and further preferably 10 hours or less.

The haloalkylation reaction described above may be performed in the same reaction system by changing the reaction temperature and / or the amount of catalyst stepwise or continuously from the first reaction stage to the second reaction stage.
[2-4] (e) A step of removing an eluting compound having a specific structure from a haloalkylated crosslinked copolymer (haloalkylated crosslinked copolymer)
In the present invention, the haloalkylated crosslinked copolymer obtained in the section [2-3] is then referred to as an eluting compound represented by the following formula (II) (hereinafter referred to as “eluting compound (II)”). The content of the eluting compound (II) is preferably 10,000 μg or less, more preferably 1,000 μg or less, particularly preferably 1 g of the haloalkylated crosslinked copolymer. It is preferable to purify the haloalkylated cross-linked copolymer so that it becomes 100 μg or less, particularly preferably 10 μg or less. When the content of the eluting compound (II) is large, it tends to be impossible to obtain an anion exchange resin with a small amount of the eluting material in which the remaining of impurities and the generation of decomposition products are suppressed. Although the content of the eluting compound (II) is preferably as small as possible, the lower limit is usually about 30 μg.

(In formula (II), X represents a hydrogen atom, a halogen atom, or an alkyl group which may be substituted with a halogen atom. Y represents a halogen atom. N and m each independently represent a natural number. )
Here, the alkyl group which may be substituted with the halogen atom of X is usually an alkyl group having 1 to 10 carbon atoms or a haloalkyl group, preferably a methyl group, an ethyl group, a propyl group, a butyl group, a halomethyl group. , A haloethyl group, a halopropyl group, and a halobutyl group, and more preferably a methyl group, an ethyl group, a halomethyl group, and a haloethyl group.

N is usually 1 or more, usually 8 or less, preferably 4 or less, and more preferably 2 or less.
In addition, the eluting compound (II) according to the present invention causes an ion exchange resin eluate at the time of product, like the eluting compound (I). The breakdown includes a substance derived from an eluting compound originally contained in the cross-linked copolymer serving as a matrix for haloalkylation and a substance generated at the stage of haloalkylation.

The substance derived from the eluting compound originally contained in the cross-linked copolymer serving as the matrix of the haloalkylation is a haloalkylated product of the eluting compound (I) described in [2-2] (d), It corresponds to the substance shown in II). In addition, substances into which a plurality of haloalkyl groups are introduced are also included.
Examples of the substance generated at the stage of haloalkylation include a substance generated along with the cleavage of the carbon-carbon bond by the reverse reaction of the Friedel-Crafts reaction, which is also represented by the above formula (II). For example, low-molecular and high-molecular polymers and oligomer components generated by cleavage of the main chain of the crosslinked copolymer.

  The weight average molecular weight of these eluting compounds (II) in terms of polystyrene sulfonic acid is usually 200 or more, preferably 300 or more, and usually 1,000,000 or less, preferably 100,000 or less. For example, in the case of a styrene resin, the eluting compound (II) is a styrene dimer, a styrene trimer, a styrene oligomer haloalkylated product as a low polymer component that is insufficiently polymerized, and a free polymer component of linear polystyrene or polystyrene fine particles. And haloalkylated compounds. Further, as a by-product in the chain transfer reaction in the polymerization reaction, there may be mentioned a haloalkylated product of a low polymer component or a free polymer component to which a polymerization inhibitor contained in the monomer is bound.

Such eluting compound (II) can be removed, for example, by washing the haloalkylated cross-linked copolymer obtained in step (b) with a solvent.
This washing method can be performed by a column method in which a haloalkylated crosslinked copolymer is packed in a column and water is passed through the solvent, or by a batch washing method.
The washing temperature is usually room temperature (20 ° C) or higher, preferably 30 ° C or higher, more preferably 50 ° C or higher, particularly preferably 90 ° C or higher, and usually 150 ° C or lower, preferably 130 ° C or lower, more preferably 120 ° C or lower. It is. If the washing temperature is too high, the polymer will be decomposed and haloalkyl groups may be removed. If the washing temperature is too low, the washing efficiency is lowered.

The contact time with the solvent is usually 5 minutes or longer, preferably the time for which the crosslinked copolymer swells 80% or more, and is usually 4 hours or shorter. If the contact time is too short, the cleaning efficiency is lowered, and if the time is too long, the productivity is lowered.
Solvents used for washing include aliphatic hydrocarbons having 5 or more carbon atoms, such as pentane, hexane, and heptane; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, diethylbenzene, and the like; alcohols such as methanol, Ethanol, propanol, butanol, etc .; ketones such as acetone, methyl ethyl ketone, etc .; ethers such as dimethyl ether, diethyl ether, methylal, etc .; chlorinated solvents such as dichloromethane, chloroform, carbon tetrachloride, dichloroethane, trichloroethane, etc .; phenols such as Such as phenol, and the like. These may be used alone or in combination of two or more. Of these, benzene, toluene, xylene, acetone, diethyl ether, methylal, dichloromethane, chloroform, dichloroethane, and trichloroethane are preferable.

[2-5] (c) A step of reacting the haloalkylated crosslinked copolymer with an amine compound
In the anion exchange resin in the present invention, it is preferable that the step (a) and the step (b) are also performed by passing through the step (a) and the step (b) as described above. .) By reacting the resulting haloalkylated cross-linked copolymer with an amine compound to produce an anion exchange resin by introducing an amino group, the introduction of the amino group can be easily carried out by a known technique. it can.

For example, a method in which a haloalkylated cross-linked copolymer is suspended in a solvent and reacted with trimethylamine or dimethylethanolamine can be mentioned.
As the solvent used in the introduction reaction, for example, water, toluene, dioxane, dimethylformamide, dichloroethane or the like is used alone or in combination.
Thereafter, the anion exchange resin can be obtained by changing the salt form to various anion forms by a known method.

  As described above, when the reaction conditions are suppressed in the haloalkylation step to control the introduction rate of the haloalkyl group, the post-crosslinking method may be weakened. As a countermeasure in this case, in the step (a), the amount of the crosslinkable aromatic monomer added in advance is larger than the amount necessary for obtaining a resin having a desired moisture content in the conventional anion exchange resin production method. A copolymer is synthesized, and then the haloalkylation introduction rate is 85% or less, preferably 80% or less, more preferably 70% or less, more preferably 50% or less, by taking the haloalkylation conditions as in the present invention, Particularly preferably, it can be suppressed to 45% or less.

By adding the above-described operation, the crosslink density of the haloalkylated cross-linked copolymer is controlled, and when the amine is reacted to form an anion exchange resin, the desired water content and strength can be obtained.
[2-6] Method for producing OH-type anion exchange resin
The OH-type anion exchange resin of the present invention can be produced by regenerating the Cl-type anion exchange resin synthesized above into a OH form by a known regeneration method.

For example, a method described in JP-A No. 2002-102719 can be suitably used.
[2-7] Purification method of OH type anion exchange resin
The OH-type anion exchange resin of the present invention is produced by producing a Cl-type or OH-type anion exchange resin by the method up to [2-6] or [2-7], and then applying a known elution reduction method to obtain an ultrapure. An anion exchange resin for water can be used.

For example, the method described in JP-A-2002-102719 can be suitably used.
Specifically, a method of heating and washing in the presence of an alkali solution, a method of washing with hot water using a column, and a method of washing with a solvent can be suitably used. Moreover, after manufacturing a Cl form or OH form anion exchange resin by the method to [2-6] or [2-7], the reduction method of a well-known metal content is also applicable as needed.

[2-8] Other processing
The anion exchange resin of the present invention obtained as described above may be further subjected to various treatments usually performed as a treatment of the anion exchange resin. For example, the anti-leaking process may be performed by a known method.
That is, in general, when an anion exchange resin is used in a mixed bed with a cation exchange resin, the mixed bed resin formed of the cation exchange resin and the anion exchange resin because of the “entanglement phenomenon” that is electrically entangled with the cation exchange resin. Since the volume of the material increases excessively, it becomes a problem in terms of handling.

  Therefore, by carrying out the anti-entanglement treatment on the anion exchange resin of the present invention, the volume increase rate when mixed with the cation exchange resin is 150% or less, preferably 130% or less, more preferably 110% or less before mixing. It is preferable to do. The volume increase rate is a percentage of the ratio of the volume of the mixed bed resin after mixing to the total volume before mixing the anion exchange resin and the cation exchange resin.

As this anti-entanglement treatment, a known method described in JP-A-10-202118 or JP-A-2002-102719 can be applied.
Specifically, it is usually 0.01 mmol / L or more, preferably 0.1 mmol / L or more, and usually 10 mmol / L or less, preferably 2 mmol / L or less per 1 liter of anion exchange resin. It can be carried out by treatment with a water-soluble polymer containing a group.

  Examples of the water-soluble polymer containing an anionic dissociation group suitable for use in the present invention include known water-soluble polymers described in JP-A-10-202118 and JP-A-2002-102719. Preferably, polystyrene sulfonic acid, polyvinyl benzyl sulfonic acid, polymaleic acid, poly (meth) acrylic acid, polyvinyl sulfonic acid and the like can be mentioned. Of these, polystyrene sulfonic acid and polyvinyl sulfonic acid are preferably used. These may be used alone or in combination of two or more.

[3] Method for Producing Ion Exchange Resin In [2], the production method in the case where the ion exchange resin of the present invention is an anion exchange resin has been described. However, according to the following method, it is limited to an anion exchange resin. And an ion exchange resin can be produced.
When manufacturing the 1st ion exchange resin of this invention, it is preferable to manufacture with the manufacturing method which has the process of following (A) and (B).
(A) When copolymerizing a mixture of a monovinyl aromatic monomer and a crosslinkable aromatic monomer, a porosifying agent is added in an amount of 100% by weight or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. To obtain a crosslinked copolymer.
(B) A step of introducing an exchange group into the cross-linked copolymer obtained in (A) so that an ion exchange group introduction rate is 70% or less.

Here, in (A), the addition amount of the porosifying agent is 105% by weight or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer, and in (B), the ion exchange The group introduction rate is preferably 50% or less.
Moreover, you may have the following (D) process between the said (A) process and the said (B) process as needed.
(D) The process which makes content of the eluting compound shown by following formula (I) 1000 micrograms or less with respect to 1 g of monovinyl aromatic monomers and a crosslinkable aromatic monomer crosslinked copolymer.

(In the formula (I), Z represents a hydrogen atom or an alkyl group. L represents a natural number.)
When manufacturing the 2nd and 3rd ion exchange resin of this invention, it is preferable to manufacture by the manufacturing method which has the process of following (A '), (B'), and (D ').
(A ′) When copolymerizing a monovinyl aromatic monomer and a crosslinkable aromatic monomer, a porosifying agent is added in an amount of 80% or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. A step of obtaining a polymer.
(D ′) A step of setting the content of the eluting compound represented by the following formula (I) to 1000 μg or less with respect to 1 g of the monovinyl aromatic monomer and the crosslinkable aromatic monomer crosslinked copolymer.

(In the formula (I), Z represents a hydrogen atom or an alkyl group. L represents a natural number.)
(B ′) A step of introducing ion exchange groups into the crosslinked copolymer obtained by reducing the eluting compound obtained in (D ′) at an ion exchange group introduction rate of 85% or less.
In addition, about the said (A) process and (A ') process, description of the (a) process described in said [2] can be used, About the said (D) process and (D') process Can use the description of the step (d) described in [2] above. Moreover, about the said (B) process and (B ') process, it is preferable to determine various conditions according to the ion exchange group to introduce | transduce.

  Moreover, when manufacturing a cation exchange resin as an ion exchange resin of this invention, about the said (B) process and (B ') process, said (A) process, (A') process, or (D ') What is necessary is just to introduce | transduce a cation exchange group into a crosslinked copolymer obtained at the process using a well-known method. When introducing a sulfonic acid group as an ion exchange group, methods described in JP-A-5-132565, JP-T-10-508061, and the like can be used.

Further, when producing a cation exchange resin as the ion exchange resin of the present invention, the step (D) or the step (D ′) corresponds to a step of washing the [2-2-6] crosslinked copolymer. It is preferable to perform the process to perform. This is because the eluting compound (I) can be removed by washing the crosslinked copolymer obtained in the step (A) or the step (A ′) with water or a solvent. Further, the sulfonated crosslinked copolymer obtained in the step (B) or (B ′) may be washed with water or a solvent.
The cleaning method is preferably as follows.

  As the washing method, the cross-linked polymer is packed in a column and passed, or a batch washing method can be used. The temperature is usually room temperature (20 ° C.) or higher, preferably 30 ° C. or higher, more preferably 50 ° C. or higher, particularly preferably 90 ° C. or higher, and usually 150 ° C. or lower, preferably 130 ° C. or lower, more preferably 120 ° C. or lower. It is. If the washing temperature is too high, the polymer may be decomposed or the sulfone group may be removed. If the cleaning temperature is too low, the cleaning efficiency tends to decrease. The contact time with the solvent is usually 5 minutes or longer, preferably 1 hour or longer, more preferably 2 hours or longer, and usually 4 hours or shorter. If the time is too short, the cleaning efficiency tends to decrease, and if the time is too long, the productivity tends to decrease.

  Solvents that can be used for washing include aliphatic hydrocarbons having 5 or more carbon atoms (eg, pentane, hexane, heptane, etc.) and aromatic hydrocarbons (eg, benzene, toluene, xylene, ethylbenzene, diethylbenzene, etc.). Preferably used. Also, alcohols (eg, methanol, ethanol, propanol, butanol, etc.), ketones (eg, acetone, methyl ethyl ketone, etc.), ethers (eg, dimethyl ether, diethyl ether, methylal, etc.), chlorinated solvents (eg, dichloromethane) , Chloroform, carbon tetrachloride, dichloroethane, trichloroethane and the like) and phenols (for example, phenol and the like) are also preferably used.

The cation exchange resin of the present invention can be purified by a known regeneration method.
[4] Demineralizer, condensate demineralizer for power plant, and method for removing suspended metal corrosion product
The desalination apparatus of the present invention is formed using the macroporous ion exchange resin of the present invention. For example, the anion exchange resin of the present invention is used by being loaded on the upper layer of a mixed bed ion exchange resin tower formed of a cation exchange resin and an anion exchange resin. Such a method of use is preferable because, in the anion exchange resin of the present invention, both the filter effect for removing the clad and the adsorption removal effect of the suspended metal corrosion product containing the clad and colloidal fine particles are expected. .

Further, the desalting apparatus of the present invention, for example, desalting described in pages 59-63 of “Diaion II Application” 15th edition (October 1, 2000) issued by Mitsubishi Chemical Corporation Ion Exchange Resin Division It can be applied as a condensate demineralizer for power plants by a known method such as an apparatus.
[4-1] Application to PWR primary system The anion exchange resin of the present invention can be used for an existing ion exchange resin tower used for desalting and purification of a primary cooling water system of a PWR nuclear power plant. Conventionally, this ion exchange resin tower has been filled with an existing mixed bed ion exchange resin of cation exchange resin and anion exchange resin. The mixed bed ion exchange resin layer has a function of capturing metal ions dissolved in water and filtering out insoluble suspended metal corrosion products. However, the ability of mixed bed ion exchange resin to collect suspended metal corrosion products is not so large, so when a large amount of suspended metal corrosion products are generated, such as when the plant is shut down or when a steam generator is replaced. Has a problem that the suspended metal corrosion product cannot be collected and leaks.

  As described above, there is a method of laminating an anion exchange resin having a high colloidal particle capturing ability on the upper layer of the mixed bed ion exchange resin for the purpose of supplementing the low colloidal particulate capturing ability of the conventional mixed bed ion exchange resin. This method has the advantage that no special plant modification is required since the existing desalting tower can be used as it is. Since the anion exchange resin of the present invention has an excellent ability to trap colloidal particles, this method can collect radioactive colloidal metal corrosion products much more effectively than the conventional lamination of ion exchange resins. is there.

  In addition, if the ion exchange resin of the present invention is used, the radioactive colloidal fine particles contained in the system water of the nuclear power plant can be collected at a high yield, so that the radioactive material does not circulate in the system water system, and It becomes possible to easily contain the causative substance in the demineralization tower of the ion exchange resin. Moreover, if the ion exchange resin of this invention is used, the conventional system | system | group water-system membrane filter will not be obstruct | occluded easily, and the replacement frequency of a membrane filter can be decreased. In addition, the frequency of manual replacement of the membrane filter clogged with radioactive material is reduced, which can contribute to a significant reduction in the radiation dose of workers at nuclear power plants. In addition, since replacement of used ion exchange resin can be handled by pump transfer, remote operation is possible, and workability and safety are remarkably improved. Furthermore, since the waste of the membrane filter with a large occupation space can be reduced, it can contribute to volume reduction of radioactive waste.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example, unless the summary is exceeded.
[1] Examples 1 to 4 and Comparative Examples 1 to 3
[Example 1]
Step (a) As a monomer layer, 168 g of styrene (industrial grade, manufactured by Idemitsu Co., Ltd.), 131 g of divinylbenzene (industrial grade, purity 57% by weight, manufactured by Nippon Steel Chemical Co., Ltd.), 359 g of isooctane (industrial grade), dibenzoyl peroxide (purity) 75 wt%, wet product (made by NOF Corporation) 7.96 g, t-butylperoxy-2-ethylhexyl monocarbonate (purity 99 wt%, NOF Corporation) 2.99 g were mixed.

Here, isooctane is used as the porosifying agent, and the amount added is 120% by weight with respect to the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer.
As an aqueous phase, 6% polyvinyl alcohol (industrial, manufactured by Nippon Synthetic Chemical Co., Ltd., polymerization degree 1,000, saponification degree 91%, for vinyl acetate emulsifier) aqueous solution 164 mL, 5% sodium bicarbonate aqueous solution 99 mL, 5 as water phase 122% aqueous sodium carbonate solution and 59 mL 1% aqueous sodium nitrite solution were mixed. The monomer phase was suspended in the aqueous phase.

The suspension was stirred at 80 ° C. for 4 hours and then reacted at 115 ° C. for 4 hours to obtain a copolymer (1).
Step (b) 150 g of the copolymer (1) was placed in a round bottom four-necked flask, and 1250 mL of chloromethyl methyl ether (purity 99%, self-made raw material) was added to sufficiently swell the copolymer. Thereafter, 180 g of zinc chloride (Kishida Chemical Reagent) was added as a Friedel-Crafts reaction catalyst, and the reaction was carried out for 10 hours with stirring at a bath temperature of 50 ° C. to obtain a chloromethylated copolymer (2).

In addition, the haloalkyl group introduction rate in this step can be determined as follows.
(Haloalkyl group introduction rate)
The exchange capacity (per 1 g of dry resin) of the obtained Cl-type anion exchange resin was 1.3 meq / g as measured by the procedure described in [2] below.

On the other hand, the monomer unit of the resin is — (CH ₂ —CH) — (C ₆ H ₄ ) — (CH ₂ ) —N (CH ₃ ) ₃ Cl (molecular weight 199.
Assuming 5), the exchange capacity per 1 g of dry resin when one exchange group is introduced into all the monomer units of the resin is 5.01 meq / g (= 1 / 199.5). .
Therefore, the exchange group introduction rate in this step can be calculated by the ratio of 1.3 and 5.01, and in this example, it was 26%.
Step (c) 454 g of the above chloromethylated copolymer (2) is placed in a round bottom four-necked flask, 629 mL of demineralized water, 250 mL of toluene (Wako Pure Chemical Industries, Ltd.), 30% by weight trimethylamine aqueous solution (reagent manufactured by Wako Pure Chemical Industries, Ltd.) ) 320 mL was added and reacted for 8 hours with stirring at 50 ° C. to obtain an I-type quaternary ammonium-type anion exchange resin (Cl-type) (3).

The column is packed with the I-type quaternary ammonium type anion exchange resin (3) obtained above, and regenerated by passing through a sodium bicarbonate aqueous solution (Wako Pure Chemicals reagent) and NaOH (Wako Pure Chemicals reagent) aqueous solution. Then, it was converted to an OH-type anion exchange resin, and finally washed with ultrapure water to obtain an OH-type anion exchange resin of Example 1.
[Example 2]
Step (a) As a monomer layer, 259 parts of styrene (industrial grade, manufactured by Idemitsu), 156 parts of divinylbenzene (industrial grade, 63% by weight, manufactured by Dow), 498 g of isooctane (industrial grade), dibenzoyl peroxide ( Purity 75% by weight, wet product (made by NOF Corporation) 6.91 parts, t-butylperoxy-2-ethylhexyl monocarbonate (purity 99% by weight, NOF Corporation) 2.65 parts were mixed.

Here, isooctane is used as the porosifying agent, and the amount added is 120% by weight with respect to the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer.
As an aqueous phase, 1791 parts of demineralized water, 48 parts of an aqueous solution of 6% polyvinyl alcohol (for industrial use, manufactured by Nippon Synthetic Chemical Co., Ltd., polymerization degree 1,000, saponification degree 91%, for vinyl acetate emulsifier), 4.6 parts of baking soda 5.7 parts of sodium carbonate and 0.55 parts of sodium nitrite were mixed. The monomer phase was suspended in the aqueous phase. The suspension was stirred at 80 ° C. for 6 hours and then reacted at 115 ° C. for 4 hours to obtain a copolymer (1).
-(B) process 150 parts of said copolymers (1) were put into the reactor, 1350 parts of chloromethyl methyl ether (purity 99%, self-made raw material) was added, and the copolymer was fully swollen. Thereafter, 180 parts of zinc chloride (Kishida Chemical Reagent) was added as a Friedel-Crafts reaction catalyst, and the reaction was carried out for 10 hours with stirring at a bath temperature of 50 ° C. to obtain a chloromethylated copolymer (2). .

Here, the exchange capacity (per gram of the dried resin) of the obtained Cl-type anion exchange resin was 1.4 meq / g as measured by the procedure described in [2] below.
In addition, the haloalkyl group introduction rate calculated by the same method as in Example 1 was 29%. Step (c) The whole amount of the above chloromethylated copolymer (2) is put into a reactor, 696 parts of demineralized water, 259 parts of toluene (Wako Pure Chemical Reagent), 30 wt% aqueous solution of trimethylamine (reagent manufactured by Wako Pure Chemical) 332 Part I was added and reacted at 50 ° C. with stirring for 8 hours to obtain an I-type quaternary ammonium-type anion exchange resin (Cl-type) (3).

The column is packed with the I-type quaternary ammonium type anion exchange resin (3) obtained above, and regenerated by passing through a sodium bicarbonate aqueous solution (Wako Pure Chemicals reagent) and NaOH (Wako Pure Chemicals reagent) aqueous solution. And converted to an OH form anion exchange resin.
Finally, it was washed with ultrapure water to obtain an anion exchange resin of Example 2.
[Example 3]
As · (a) step the monomer layer, styrene (technical grade, Idemitsu Co.) 208g, divinylbenzene (technical grade, purity 57 wt%, Nippon Steel Chemical Co., Ltd.) 162 g, polystyrene (molecular weight 4 × ¹⁰ 4) 111g, Toluene ( 445 g of Wako Pure Chemicals Reagent grade 1) and dibenzoyl peroxide (purity 75% by weight, wet product, manufactured by NOF Corporation) were mixed.

Here, polystyrene and toluene are used as the porosifying agent, and the addition amount is 150% by weight with respect to the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer.
As an aqueous phase, 1366 mL of demineralized water was mixed with 83 mL of a 6% polyvinyl alcohol (industrial, Nippon Synthetic Chemicals, Grade GH20) aqueous solution, 170 mL of 5% sodium bicarbonate aqueous solution, and 50 mL of 1% sodium nitrite aqueous solution. The monomer phase was suspended in the aqueous phase.

The suspension was reacted at 80 ° C. for 8 hours with stirring to obtain a copolymer (1).
Step (b) and Step (c) Thereafter, in the same manner as in Example 1, an I-type quaternary ammonium type anion exchange resin (Cl-type) (3) was obtained, and then the I-type quaternary ammonium obtained above. Type anion exchange resin (3) is packed in a column and regenerated by passing through a sodium bicarbonate aqueous solution (Wako Pure Chemicals reagent) and NaOH (Wako Pure Chemicals reagent) aqueous solution to convert to an OH type anion exchange resin. Finally, it was washed with ultrapure water to obtain an anion exchange resin of Example 3.

The exchange capacity (per gram of dry resin) of the obtained Cl-type anion exchange resin was 2.3 meq / g as measured by the procedure described in [2] below.
The haloalkyl group introduction rate calculated by the same method as in Example 1 was 46%.
[Example 4]
Step (a) As a monomer layer, 168 g of styrene (industrial grade, manufactured by Idemitsu Co., Ltd.), 131 g of divinylbenzene (industrial grade, purity 57% by weight, manufactured by Nippon Steel Chemical Co., Ltd.), 359 g of isooctane (industrial grade), dibenzoyl peroxide (purity) 75 wt%, wet product (made by NOF Corporation) 7.96 g, t-butylperoxy-2-ethylhexyl monocarbonate (purity 99 wt%, NOF Corporation) 2.99 g were mixed.

Here, isooctane is used as the porosifying agent, and the amount added is 120% by weight with respect to the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer.
As an aqueous phase, 164 mL of a 6% polyvinyl alcohol (industrial, manufactured by Nippon Synthetic Chemical Co., Ltd.) aqueous solution 164 mL, 5% sodium bicarbonate aqueous solution 99 mL, 5% sodium carbonate aqueous solution 122 mL, and 1% sodium nitrite aqueous solution 59 mL were mixed with 1526 mL of demineralized water. The monomer phase was suspended in the aqueous phase.

The suspension was reacted at 80 ° C. for 8 hours with stirring to obtain a copolymer (1).
Step (b) 150 g of the copolymer (1) was placed in a round bottom four-necked flask, and 1250 mL of chloromethyl methyl ether (purity 99%, self-made raw material) was added to sufficiently swell the copolymer. Thereafter, 180 g of zinc chloride (Kishida Chemical Reagent) was added as a Friedel-Crafts reaction catalyst, and the reaction was carried out for 10 hours with stirring at a bath temperature of 50 ° C. to obtain a chloromethylated copolymer (2).

Here, the exchange capacity (per 1 g of the dried resin) of the obtained Cl-type anion exchange resin was measured by the procedure described in [2] below, and was 1.7 meq / g.
The haloalkyl group introduction rate calculated by the same method as in Example 1 was 34%. Step (c) 454 g of the above chloromethylated copolymer (2) is placed in a round bottom four-necked flask, 629 mL of demineralized water, 250 mL of toluene (Wako Pure Chemical Industries, Ltd.), 30% by weight trimethylamine aqueous solution (reagent manufactured by Wako Pure Chemical Industries, Ltd.) ) 320 mL was added and reacted for 8 hours with stirring at 50 ° C. to obtain an I-type quaternary ammonium-type anion exchange resin (Cl-type) (3).

A column is filled with the type I quaternary ammonium type anion exchange resin obtained above, and regeneration is performed by passing through an aqueous sodium bicarbonate solution (a reagent manufactured by Wako Pure Chemical Industries) and an aqueous solution of NaOH (a reagent manufactured by Wako Pure Chemical Industries). It was converted into a form anion exchange resin, and finally washed with ultrapure water to obtain an OH form anion exchange resin.
[Comparative Example 1]
A commercially available anion exchange resin “HPA25L” manufactured by Mitsubishi Chemical Corporation was used. The regeneration of the resin was performed in the same manner as in Example 1.

Here, the exchange capacity (per gram of the dried resin) of the Cl-type anion exchange resin used in Comparative Example 1 was 2.9 meq / g as measured by the procedure described in [2] below.
The haloalkyl group introduction rate calculated by the same method as in Example 1 was 57%.
[Comparative Example 2]
A commercially available anion exchange resin “PA312LT” manufactured by Mitsubishi Chemical Corporation was used. The regeneration of the resin was performed in the same manner as in Example 1.

Here, the exchange capacity (per gram of dry resin) of the Cl-type anion exchange resin used in Comparative Example 2 was 4.0 meq / g as measured by the procedure described in [2] below.
In addition, the haloalkyl group introduction rate calculated by the same method as in Example 1 was 80%.
[Comparative Example 3]
· (A) as a step monomer layer, styrene (technical grade) 197 parts of divinylbenzene (technical grade, purity 57 wt%, manufactured by Nippon Steel Chemical Co., Ltd.) 42 parts, polystyrene (molecular weight 4 × ¹⁰ 4) 84 parts of toluene (total 120 parts of Reagent grade 1 manufactured by Kojun Pharmaceutical Co., Ltd. and 3.1 parts of dibenzoyl peroxide (purity 75% by weight, wet product, manufactured by NOF Corporation) were mixed.

Here, polystyrene and toluene are used as the porosifying agent, and the addition amount is 85% by weight with respect to the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer.
As an aqueous phase, 1800 parts of demineralized water was mixed with 110 parts of a 6% polyvinyl alcohol (industrial, manufactured by Nippon Synthetic Chemical) aqueous solution, 225 parts of a 5% aqueous sodium bicarbonate solution, and 66 parts of a 1% aqueous sodium nitrite solution. The monomer phase was suspended in the aqueous phase.

The suspension was reacted at 80 ° C. for 8 hours with stirring to obtain a copolymer (1).
Step (b) and Step (c) Thereafter, in the same manner as in Example 1, an I-type quaternary ammonium type anion exchange resin (Cl type) (3) was obtained, and then the I-type quaternary ammonium obtained above. Type anion exchange resin (3) is packed in a column and regenerated by passing through an aqueous solution of sodium bicarbonate (a reagent manufactured by Wako Pure Chemical) and an aqueous solution of NaOH (a reagent manufactured by Wako Pure Chemical) to convert it into an OH type anion exchange resin. Finally, it was washed with ultrapure water to obtain an anion exchange resin.

Here, the exchange capacity (per 1 g of dry resin) of the obtained Cl-type anion exchange resin was measured by the procedure described in [2] below, and was 3.4 meq / g.
The haloalkyl group introduction rate calculated by the same method as in Example 1 was 67%.
[2] Physical property measurement
The physical properties of the examples and comparative examples were measured as follows. The results are shown in Table 1.

[2-1] Average pore radius
The vacuum-dried ion exchange resin was placed in a glass cell, and the pore radius was measured with a mercury porosimeter / autopore 9500 type apparatus manufactured by Micromeritics. A histogram showing the distribution of pores with the pore volume and pore radius as the vertical axis and the horizontal axis, respectively, was created, and the pore radius of the portion with the largest total pore volume was taken as the average pore radius.

[2-2] Pore volume
The vacuum-dried ion exchange resin was placed in a glass cell, and the pore volume was measured with a mercury porosimeter / autopore 9500 type apparatus manufactured by Micromeritics.
The pore volume per mL of wet resin was calculated by dividing the pore volume measured in the dry state by the degree of swelling (per 1 g of dry resin).

<Calculation formula>
(Pore volume per mL of wet resin (unit mL / mL))
= (Pore volume per 1 g of resin in dry state (unit mL / g)) / (swelling degree (per 1 g of dry resin (unit mL / g))
In addition, the value calculated | required by the method as described in a below-mentioned [2-13] swelling degree was used for the swelling degree in the said formula.

[2-3] Exchange capacity and moisture
<Exchange capacity and moisture measurement of Cl-type anion exchange resin>
Measured by using a known calculation method described in pages 142 to 148 of “Diaion I Fundamentals” 14th edition (September 1, 1999) issued by Mitsubishi Chemical Corporation Ion Exchange Resin Division. 10 mL of Cl-type anion exchange resin was collected and regenerated by flowing 750 mL of 2N-NaOH aqueous solution. Next, after washing with demineralized water to neutrality, 250 mL of 5% saline was flowed to collect all the effluent. By titrating the effluent with hydrochloric acid, the exchange capacity (meq / mL) per volume of the ion exchange resin was calculated.

Next, the Cl-type anion exchange resin was centrifuged to remove the adhering water, and the weight was measured. Then, it dried for about 4 hours in a 105 ± 2 degreeC thermostat. After standing to cool in a desiccator, the weight was measured and the water content (% by weight) was calculated.
The exchange capacity per dry weight of the Cl-type anion exchange resin was calculated by the following equation using the apparent density measured by the BSD method in [2-5].

(Meq / g) = (meq / mL) × 1000 / apparent density × 100 / (100−water%)
<Exchange capacity and moisture measurement of OH type anion exchange resin>
10 ml of an OH-type anion exchange resin was taken and 25% of a 5% NaCl aqueous solution was passed through to collect all the effluent. By titrating the effluent with hydrochloric acid, the exchange capacity (meq / mL) per volume of the ion exchange resin was calculated.

The water content was measured by centrifuging the OH-type anion exchange resin to remove the adhering water, and then using a digital automatic titrator (equivalent to Karl Fischer KF07 model manufactured by Mitsubishi Chemical) by the Karl Fischer method.
The exchange capacity per dry weight of the anion exchange resin was calculated by the following formula using the apparent density measured by the BSD method in [2-5].

(Meq / g) = (meq / mL) × 1000 / apparent density × 100 / (100−water%)
[2-4] Specific surface area
The vacuum-dried ion exchange resin was measured for the specific surface area per dry weight of the ion exchange resin with a specific surface area meter (Flowsorb 2300 manufactured by Shimadzu Corporation).

[2-5] Apparent density
(I) Tap method
About 150 g of sample was taken and weighed accurately. Next, it was put into a 500 mL graduated cylinder with demineralized water, the bottom was tapped until the volume was not reduced, and the volume VmL was read.

The apparent density was calculated by the following formula.
Apparent density (g / L) = Weighed sample weight (g) / V × 1000
(Ii) BSD method
Approximately 150 g of sample was taken and accurately weighed. This was transferred to a measuring tube containing demineralized water in advance. Next, demineralized water was flowed from the bottom at a rate of 50 to 60% of bed expansion, and backwashing was performed until the resin surface was in equilibrium. Next, after stopping the desalted water and allowing to stand for 2 minutes, the water in the measuring tube is drawn from the bottom at a speed of LV = 9 to 15 m / hr until the water surface remains about 10 mm above the resin layer surface, and the resin after standing for 1 minute. The capacity was read, and the apparent density was determined by the formula described in (i) Tap method.

[2-6] True specific gravity
The weight of the dried pycnometer with thermometer was measured (this weight is referred to as “Ag”). Next, about 1/3 of the resin was put into a pycnometer and the whole weight was measured (this weight is referred to as “Bg”).
The pycnometer was filled with demineralized water and immersed in a thermostatic bath set at 25 ° C. When the internal temperature reached 25 ° C., water was drawn out to the marked line with a syringe, stoppered, and taken out from the thermostatic bath. The moisture outside the pycnometer was wiped off and weighed (this weight is referred to as “Cg”).

Next, the resin and demineralized water of the same pycnometer were extracted, and only demineralized water was added and immersed in a thermostatic bath. When the temperature reached 25 ° C., the water was drawn out to the marked line with a syringe and stoppered, and then removed from the thermostatic bath. The moisture outside the pycnometer was wiped off and weighed (this weight is hereinafter referred to as “Dg”).
The true specific gravity was calculated by the following formula.

True specific gravity = (B−A) × DW / ((D−A) + (B−A) − (C−A))
DW: Demineralized water density at 25 ° C
[2-7] Weight average particle diameter The weight average particle diameter was calculated by the “weight average particle diameter measurement method” in [1-4] of “Mode for Carrying Out the Invention” of the present specification.

[2-8] Effective particle size
The weight average particle size was calculated by the effective particle size measurement method described in “Method for measuring uniformity coefficient” in [1-5] of “Mode for Carrying Out the Invention” of this specification.
[2-9] Uniformity coefficient
The weight average particle diameter was calculated by the “uniformity measurement method” in [1-5] of “Mode for Carrying Out the Invention” of this specification.

[2-10] Strength (turbidity after shaking)
[Turbidity removal test after shaking]
An amount equivalent to 10 mL of ion exchange resin was weighed into a flask, ultrapure water was added to 100 mL, and the flask was capped and shaken at 100 rpm for 20 hours in a constant temperature bath kept at 40 ° C. Thereafter, supernatant water was collected, and turbidity was measured with an integrating sphere turbidity meter manufactured by Mitsubishi Chemical.

The values of OH type and Cl type shown in Table 1 were obtained by the above method.
[2-11] Elution amount
<Elution amount measurement method>
An amount equivalent to 10 mL of ion exchange resin (OH form) was weighed into a flask, ultrapure water was added to 100 mL, and the flask was capped and shaken at 100 rpm for 20 hours in a constant temperature bath kept at 40 ° C. Thereafter, the supernatant water was collected, and the elution amount (TOC) was measured with a TOC measuring device “TOC5000A” manufactured by Shimadzu Corporation.

[2-12] Oxidation resistance TOC dissolution test
An amount equivalent to 10 mL of ion exchange resin was weighed into a flask, 0.1% hydrogen peroxide solution was added to 100 mL, and the flask was stoppered and shaken at 100 rpm for 20 hours in a thermostatic bath maintained at 40 ° C. Thereafter, supernatant water was collected, and 0.1% H ₂ O ₂ elution TOC was measured with a TOC measuring device “TOC5000A” manufactured by Shimadzu Corporation.

[2-13] Swelling degree The swelling degree is a resin volume when 1 g of a resin in a dry state is brought into a water wet state. Dividing the value of ion exchange capacity per volume (meq / mL) in the case of Cl form measured in [2-3] above by the value of ion exchange capacity per unit weight (meq / g) in the case of Cl form. Calculated.
<Calculation formula>
Swelling degree (per 1 g of dry resin (unit: mL / g))
= Wet resin volume (mL) / (weight per gram of dry resin (g))
= (Meq / g) / (meq / mL)
[3] Suspension metal corrosion product removal performance evaluation
[3-1] Fine particle removal test
An anion exchange resin is packed in a column with an inner diameter of 20 mm so that the packing height is 200 mm, and magnetite (Fe ₃ O ₄ ) particles (manufactured by High Purity Chemical Laboratory Co., Ltd., average diameter: 1.4 μm, distribution: 0.5 to Suspension water in which 3 μm) was dispersed at a concentration of 10 ppm was passed at a flow rate of 300 mL / min. After the start of water flow, water at the column inlet and outlet was collected every predetermined time, aqua regia was added to dissolve the magnetite, and the iron concentration was quantified by the ICP-MS method.

The DF value was calculated by the following formula.
DF = Fe concentration at the column inlet / Fe concentration at the column outlet
Table 1 shows the DF value of Fe ₃ O ₄ particles 90 minutes after the start of water flow. In the examples, a higher DF value was shown than in the comparative example. Further, the total amount of Fe ₃ O ₄ particles collected was higher in the example than in the comparative example.

FIG. 1 shows the change over time in the DF value when the water passage time is taken on the horizontal axis and the DF value is taken on the vertical axis. In Example 2, it turns out that a high DF value is stably shown compared with Example 3 and a reference example (mixed bed ion exchange resin). In addition, after passing 90 minutes, the breakthrough point was reached in Example 3, whereas the DF value exceeded 10 in Example 2 and the ability to capture colloidal fine particles was maintained. Recognize. Moreover, in Example 3, although the DF value 90 minutes after the start of water passage was broken through, the total amount of Fe ₃ O ₄ particles collected was good.

In addition, the reference example plots the measurement result of the existing mixed bed ion exchange resin Diaion (registered trademark) SMN1. The resin of the reference example is a normal gel ion exchange resin, and is a resin that does not have significant pores even when the pore physical properties are measured. In the reference example, it can be seen that the collection of Fe ₃ O ₄ particles is insufficient. The ion exchange resin having no pores as in this reference example is considered to have insufficient trapping of colloidal particles because there is no collection site of colloidal particles.

[3-2] Total of magnetite (Fe ₃ O ₄ ) particle trapping amount In the particulate removal test performed in [3-1], based on the concentration difference between the inlet and the outlet of the ion exchange resin column, the ion exchange resin column The total amount of magnetite trapped by was calculated.

[3-2] SEM and EPMA image observation The SEM / EPMA image observation is carried out by the suspension metal corrosion product removal test described in [1-18] of "Best Mode for Carrying Out the Invention" of this specification. After this, the ion exchange resin was taken out of the column, the surface was observed with SEM and EPMA, and the adhesion state of the magnetite particles was observed.

FIG. 2 shows SEM and EPMA images of the surface of the ion exchange resin of Example 1 after the fine particle removal test. The magnetite particles entered the concave portion of the resin surface and were observed in a collective state in which the particles were connected to each other with the entering particles as nuclei.
[3-2] Pressure loss A glass column with a jacket having a diameter of 20 mm was filled with an amount equivalent to 157 mL of ion exchange resin, the liquid was passed in a downward flow, and the pressures at the top and bottom of the column were measured. The pressure loss was calculated by converting the pressure difference between the column inlet and the outlet per 1 m of layer height of the ion exchange resin, as in the following equation.

Pressure loss (MPa / m-bed) = (Column inlet pressure-Column outlet pressure) / (Layer height of ion exchange resin)
FIG. 3 shows the linear velocity (m / hr) on the horizontal axis and the pressure loss (MPa / m-bed) on the vertical axis. Example 2 and the existing mixed bed ion exchange resin Diaion (registered trademark) as a reference example. ) The measurement result of SMN1 was plotted. In addition, assuming an actual demineralization tower lamination, a plot is also shown when the anion exchange resin of Example 2 is laminated on the upper layer 20%, and the remaining 80% is laminated with the existing mixed bed ion exchange resin. It was.

As shown in FIG. 3, the pressure loss of the anion exchange resin of Example 2 was about twice that of the mixed bed ion exchange resin of the reference example. Further, the pressure loss when the anion exchange resin of Example 2 was laminated on the upper layer 20% and the remaining 80% was laminated with the existing mixed bed ion exchange resin was 1.2 of the mixed bed ion exchange resin of the reference example. It was about twice.
[3-3] in the column of the adsorption zone inner diameter 20 mm, packed with the anion exchange resin so that the packing height 200 mm, magnetite _(Fe 3 _{O 4)} particles (Kojundo Chemical Laboratory Co., Ltd., average diameter of 1. Suspended water in which 4 μm, distribution 0.5 to 3 μm) was dispersed at a concentration of 10 ppm was passed at a flow rate of 300 mL / min. 90 minutes after the start of water flow, water at the column inlet, the center of the column, and the column outlet were collected, aqua regia was added to dissolve the magnetite, and the iron concentration was quantified by ICP-MS method.

  Table 2 shows the concentration of iron contained in the water collected from the upper, middle, and lower parts of the column at the end of water flow (when 90 minutes have passed since the water flow started).

As shown in Table 2, the iron concentration in the center of the column was detected at 2.2 ppm in Example 3, and the tendency for iron to reach the center of the column was observed.
On the other hand, in Example 2, both the central part of the column and the lower part of the column are 0.4 ppm, indicating that a low concentration can be maintained. This indicates that the adsorption band of iron stays up to the top of the column in Example 2 and does not easily break through.

[3-4] Particle Size Distribution The particle size distribution was measured by the method described in [1-12] of “Mode for Carrying Out the Invention” of this specification.
As a result of measuring the particle size distribution of Example 2 and Example 3, the particle size distribution of 16-40 mesh is ≧ 90%, (420-1190 μm), the particle size distribution below 16 mesh is ≦ 5%, and the particle size distribution above 40 mesh is ≦ It was 5%, and all were equivalent to existing ion exchange resins.

Claims (16)

A macroporous ion exchange resin,
The pore volume as measured by the mercury intrusion method is 0.5 mL / g or more per 1 g of the dry weight of the ion exchange resin,
The pore radius when measured by the mercury intrusion method is 0.1 μm or more, and
An ion exchange resin, wherein a turbidity component eluted in a shaking turbidity test of the ion exchange resin is 45 ppm or less. 2. The ion exchange resin according to claim 1, wherein a pore volume as measured by a mercury intrusion method is 0.20 mL / mL or more per volume in a water-wet state. 3. The ion exchange resin according to claim 1, wherein the specific surface area is 5 m ² / g or more per 1 g of the dry weight of the ion exchange resin. The ion exchange resin according to any one of claims 1 to 3, wherein the ion exchange capacity is 0.01 meq / mL or more and 0.4 meq / mL or less. A macroporous ion exchange resin,
The ion exchange capacity is 0.4 meq / mL or less,
An ion exchange resin characterized by having a pore volume as measured by a mercury intrusion method of 0.1 mL / g or more per 1 g of dry weight of the ion exchange resin. The specific surface area is 5 m ² / g or more per 1 g of dry weight of the ion exchange resin,
An ion exchange resin characterized by having an average pore radius of 0.1 μm or more and 1 μm or less as measured by mercury porosimetry. The ion exchange resin according to any one of claims 1 to 6, wherein the weight average particle diameter is 0.7 mm or less. The ion exchange resin according to any one of claims 1 to 7, wherein the uniformity coefficient is 1.2 or more. The ion exchange resin according to any one of claims 1 to 8, wherein an apparent density measured by a BSD method is 650 g / L or less. A method for producing a macroporous ion exchange resin, comprising the following steps (A) and (B):
(A) When copolymerizing a mixture of a monovinyl aromatic monomer and a crosslinkable aromatic monomer, a porosifying agent is added in an amount of 100% by weight or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. Step (B) of obtaining a crosslinked copolymer by introducing the exchange group into the crosslinked copolymer obtained in (A) so that the ion exchange group introduction ratio is 70% or less. Having the following steps (a) to (c):
A method for producing a macroporous anion exchange resin.
(A) When copolymerizing a mixture of a monovinyl aromatic monomer and a crosslinkable aromatic monomer, a porosifying agent is added in an amount of 100% by weight or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. Steps (b) and (b) for obtaining a crosslinked copolymer haloalkylation obtained in steps (c) and (b) for haloalkylating the crosslinked copolymer obtained in (a) so that the haloalkyl group introduction rate is 70% or less. Reacting the crosslinked copolymer with an amine compound In (a), the addition amount of the porosifying agent is 105% by weight or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer, and
The method for producing a macroporous anion exchange resin according to claim 11, wherein, in (b), the haloalkyl group introduction rate is 50% or less. The manufacturing method of the macroporous type anion exchange resin characterized by including the process of following (a ')-(d').
(A ′) When copolymerizing a monovinyl aromatic monomer and a crosslinkable aromatic monomer, a porosifying agent is added in an amount of 80% or more per weight of the mixture of the monovinyl aromatic monomer and the crosslinkable aromatic monomer. Step of obtaining a polymer
(D ′) a step of setting the content of the eluting compound represented by the following formula (I) to 1000 μg or less with respect to 1 g of the monovinyl aromatic monomer and the crosslinkable aromatic monomer crosslinked copolymer.

(In the formula (I), Z represents a hydrogen atom or an alkyl group. L represents a natural number.)
(B ′) The haloalkylated crosslinked copolymer obtained in the step (c ′) of haloalkylating the crosslinked copolymer obtained by reducing the eluting compound obtained in (d ′) at a haloalkyl group introduction rate of 85% or less. Reacting the coalescence with an amine compound A desalinator formed using the ion exchange resin according to any one of claims 1 to 9. A condensate demineralizer for power plants, which is formed using the ion exchange resin according to any one of claims 1 to 9. A method for removing a suspended metal corrosion product, wherein the ion exchange resin according to any one of claims 1 to 9 is used.

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